فهرست مطالب علی باغبانزاده

Feeding behavior is regulated via a complex network which interacts via diverse signals from central and peripheral tissues. The present study was designed to examine the interaction between glutamatergic and dopaminergic systems on food intake in neonatal meat chicken.

In this study, 264 day-old chicken (ROS 308) were used. In each experiment, chickens divided to 4 experiments including 1 control and 3 treatment groups (n = 11). In experiment 1, chicks ICV injected with normal saline, 6-OHDA (neurotoxin, 2.5 nmol), kainic acid (ionotropic glutamate receptors agonist, 300 nmol) and 6-OHDA + kainic acid. Experiments 2-3 were similar to experiment 1, except injections of the SHC23390 (D1 receptors antagonist, 5 nmol) and AMI-193 (D2 receptors antagonist, 5 nmol) were done instead of 6-OHDA. In experiment 4, saline, 6-OHDA (2.5 nmol), trans-(±)-ACPD monohydrate (metabotropic glutamate receptor agonist, 300 nmol) and co-injection of the 6-OHDA+ trans-(±)-ACPD monohydrate were done. Experiments 5 and 6 were similar to experiment 4, except SHC23390 and AMI-193  were injected instead of 6-OHDA. Then the cumulative food intake measured until 120 min post injection.

Kainic acid significantly decreased food intake (p ≤ 0.05). 6-OHDA and SHC23390 decreased kainic acid and trans-(±)-ACPD- induced hypophagia (p ≤ 0.05).

Interaction between dopaminergic and glutamatergic systems mediates via ionotropic and metabotropic glutamate and D1 dopamine receptors.
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Serotonin (5-HT) plays an underpinning role in appetite regulation and the opioid system has a role in the modulation of the ingestion behavior in birds. The current survey was aimed to evaluate the effect of opioid receptors on serotonin-induced hypophagia in neonatal broilers. During experiments, food-deprived chickens received intracerebroventricular (ICV) injection and thereafter, the cumulative food intake was measured after 30, 60, and 120 minutes. In experiment 1, to determine the effective dose of serotonin, the control solution and the various doses of serotonin (2.5, 5, and 10 μg) were administered to birds. In the second experiment, groups received not only the control solution, but also an effective dose of serotonin (10 µg), µ-opioid receptor antagonist (β_FNA, 5 µg), and a co-injection of β_FNA (5 µg) and serotonin (10 µg), respectively. The next experiments were similar to the second experiment, however, in place of β_FNA, the antagonist of κ- opioid receptor (nor_BNI, 5 µg), the δ- opioid receptor antagonist (NTI, 5 µg), and the agonist of µ opioid receptor (DAMGO, 62.25 pmol) were used in experiments 3, 4, and 5, respectively. The results showed a dose-dependent hypophagic impact of serotonin. This effect was attenuated by β_FNA; however, nor_BNI and NTI had no effect. Furthermore, the diminishing effect of serotonin on food consumption in chickens was strengthened following DAMGO administration (p < 0.05). According to the results, the hypophagic effect of serotonin is possibly mediated through µ opioid receptors in neonatal broilers.

Various neurochemical pathways are participating in the regulation of food intake in mammals and birds. Both oxytocin (OT) and nitric oxide (NO) are known as hypophagic agents in birds. This study consisted of 6 experiments and each experiment had 4 groups (ngroup=11, 5-day-old chickens). In all experiments, 3-hour food-deprived (FD3) birds received intracerebroventricular (ICV) injections either control diluent or drug solution. Then the birds had ad libitum access to the food and fresh water and then cumulative food intake (gr) was measured based on the percentage of the body weight (%BW). In experiments 1 to 3, ICV injections of L-arginine (precursor of NO, 200, 400, and 800 nmol), L-NAME (NOS inhibitor, 100, 200, and 400 nmol) and OT (2.5, 5, and 10 µg) were performed respectively. In experiment 4, each group received any ICV injections of L-NAME (100 nmol), OT (10 µg) or a co-injection of L-NAME (100 nmol) and OT (10 µg). In experiment 5, L-arginine (ICV, 200 nmol), OT (10 µg), or L-arginine (200 nmol) and OT (10 µg) were injected to the groups. Experiment 6 was similar to the experiment 5, although the dose of OT was 2.5 µg in all the treatment groups. Results showed that the ICV injection of L-NAME (100 nmol) significantly attenuated hypophagic effect induced by OT (10 µg) (p < 0.05). Findings suggested that NO might mediate the hypophagic effect of OT in FD3 neonatal layer-type chickens.

Feeding behavior is regulated by a complex network which interacts via diverse signals from central and peripheral tissues. It is known dopaminergic and glutamatergic systems have crucial role on food intake regulation but scarce reports exist on their interaction in appetite regulation in broilers.
The present study was designed to examine the role of glutamatergic system on dopamine-induced hypophagia in neonatal meat-type chicken.
In experiment 1, chicks received ICV injection of control solution, dopamine (40 nmol), MK-801 (NMDA glutamate receptors antagonist, 15 nmol) and co-injection of dopamine MK-801. In experiment 2, birds were ICV injected with saline, dopamine (40 nmol), CNQX (AMPA glutamate receptors antagonist, 390 nmol) and co-injection of dopamine CNQX. In experiment 3, chicks received ICV injection of control solution, dopamine (40 nmol), AIDA (mGLUR1 glutamate receptors antagonist, 2 nmol), dopamine AIDA. Experiments 4 and 5 were similar to experiment 3, except birds were injected with LY341495 (mGLUR2 glutamate receptors antagonist, 150 nmol) and UBP1112 (mGLUR3 glutamate receptors antagonist, 2 nmol) instead of AIDA. Then the cumulative food intake was measured until 120 min post injection.
According to the results, ICV injection of dopamine significantly decreased food intake (p These results suggest dopamine-induced hypophagia is mediated via NMDA and mGlu1 receptors in chicken.

In vitro model studies are becoming increasingly popular for experimental research designs. They include isolation and expansion of cells of a particular tissue, such as the nervous tissue which contributes to understanding the underlying mechanisms in many pathologies. It enables the scrutinization of intracellular signaling pathways responsible for cell death. In the literature, there are different methods for the isolation and culture of rat embryonic cortical neurons. However, this study developed a feasible, rapid and easily performable method. Isolation of neurons was performed without using enzymatic digestion. Primary cortical cultures neurite outgrowth and neuron numbers per field of common mediums were compared for neuronal cells isolation and expansion. In this study, three different culture mediums were considered: Medium I: Neurobasal medium, B-27 and L-glutamine; Medium II: DMEM, FBS and L-glutamine; and Medium III: DMEM/F-12, FBS and L-glutamine. High survival rate and number of neurons was obtained with the current method. The best neuronal growth was achieved by Medium I, while Medium II and III had moderate effect on the neurite outgrowth. Enzyme-free treatment was introduced and Medium I was used as an alternative method for optimal neuron isolation and expansion. The neuronal cultures are similar to nervous tissue in physiological aspects. Hence, Medium I is more similar to the in vivo condition compared to Mediums II and III.

Glycine is an inhibitory neurotransmitter in central nervous system and plays a certain role in food intake in mammalian. The purpose of the present study was to investigate the role of glycine in central regulation of feed intake of broiler cockerels (Ross 308) during six sequential phases. At 1, 2 and 3 phases, glycine (50, 100 and 200 nmol), NFPS (inhibitor of glycine transporter at 25, 50 and 100 nmol) and hydrochloride strychnine (competitive antagonist of presynaptic of glycine at 10, 50 and 250 nmol) were injected intracerebroventriculary (ICV). At 4, 5 and 6 phases, the effect of pretreatment of NFPS (100 nmol), strychnine (250 nmol) and DL-AP5 (antagonist of glutamate NMDA receptors, 5 nmol) on cumulative feed intake induced by glycine was evaluated. During this study, the control group was injected ICV by sterile physiological serum. Thereafter, Cumulative feed intake was measured at 15, 30, 60, 120 and 180 min after injection. According to the results, ICV injection of 200 nmol glycine significantly reduced the feed intake (p<0.05). Moreover, the injection of NFPS at 50 and 100 nmol, significantly increased the feed intake (p<0.05), while strychnine had no effect. Additionally, pretreatment with NFPS and DL-AP5 significantly attenuated the feed intake induced by glycine (p<0.05), whereas strychnine had no effect (p>0.05). These results showed that the inhibitory effect of glycine on feed intake is not associated with neurotransmitory function of glycine, but is due to its neuromodulatory effect which is probably mediated via NMDA glutamate receptors in birds.

Adaptation to changes in environmental salinities have been widely studied in different euryhaline fish species but there has been less interest in studies on freshwater stenohaline fish adaptation to saline environments. Common carp, Cyprinus carpio is a suitable species to assess the effects of changes in salinities on stenohaline fish. 90 individuals of Common carp (986±0.36 g) were distributed in 6 experimental groups exposed to different salinities of 3, 6, 9, 12 and 15 g/l and a control group. At the end of the experimental period gill tissue from each experimental group was sampled and fixed in 4% paraformaldehyde. Immunolocalization of Na+-K+ ATPase was assayed by monoclonal antibody against α5 subunit of this protein (Hybridoma, USA) in 5 µm sections. Based on the results obtained mitochondria rich cells (MRCs) were present in the epithelium of both lamella and filament but after adaptation to increased salinities these type of epithelial cells (MRCs) were observed only in the epithelium of gill filament and their densities increased as an response to increasing in environmental salinities (P<0.05).

Endocannabinoid system play a critical role in the regulation of appetite in mammals. In the present study، the effect of avian brain CB1 receptor on food intake of broilers was studied. ACEA، a potent CB1 agonist، and AM281، a potent CB1 antagonist، were injected into the chicken right lateral cerebral ventricle and food intake was measured 15، 30، 60، 120، and 180 minutes post injection. The results indicate that CB1 agonist and antagonist increase and decrease food intake، respectively. Also، pretreatment with CB1 antagonist fully inhibits the CB1-agonist-induced food-intake. The results of the study is consistent with the experiments carried out in mammals.

Cholestasis stops the flow of bile from the liver to the deudenum. Cholestasis is associated with the over production of endogenous nitric oxide (NO), and water intake disturbances are commonly encountered in these patients. The purpose of this study was to determine whether elevation of endogenous NO effects on water intake alterations in cholestatic pationts. 42 mature male rats were randomly divided into 7 groups (N=6)one control group (C), three sham B (B1, B2, B3), and three experimental groups A (A1, A2, A3). After preparation and anesthesia, double ligations were placed on common bile duct in experimental groups, and a loose ligation was done on common bile duct in sham groups. In subgroups A1 and B1, Aminoguanidine (100 mg/kg, IP, for 21 days), in subgroups A2 and B2, N-nitro-L arginine methyl ester (L-Name) (10 mg/kg, IP, for 21 days) and in subgroups A3 and B3 and group C, normal saline 0.9% (the same volume, IP, for 21 days) was administrated. Water intake volume in all groups were detected daily. Data was analysed by Tukey's test and ANOVA. Statistical analysis showed that water intake increased in subgroup A1 and A2 (p

Fluctuations in salinity impose stress on the physiology of the exposed fish population and can modify their structure. It has been noted that changes in blood characteristics and plasma levels serve as the primary link between environmental change and physiological response (McCormick, 2001). Ninety healthy adult Cyprinuscarpio (C. carpio) were randomly divided into five groups and kept in salinities of 1 (control group), 3, 6, 9, 12 and 15 g/L The salinity was gradually increased by 3 g/L daily to final their concentrations. Fish were kept for 14 days after transference to the final salinity. Subsequently, plasma glucose, lactate, and protein content, as well as hematological parameters, were evaluated. The highest hematocrit (Hct), hemogloblin level (Hb), red blood cell count (RBC), lactate, and glucose values were found fish kept in the highest salinity. The values of the white blood cell count (WBC) showed an initial increase in fish from the control group until a salinity of 9 g/L, but subsequently decreased at higher salinities. The plasma protein levels among the fish in different groups did not show a significant change. The results demonstrate that changes in blood parameters can be used as indices to monitor the effects of salinity on the physiology of C. carpio.

Leptin, hormonal product of the ob gene, is known to regulate food intake, energy metabolism and reproductive functions in mammals. The mechanism by which leptin affect male reproductive system, in contrast to its well proven effects in female fertility, has been a matter of debate. Expression of leptin and its receptor in some reproductive organs suggest that leptin has both endocrine and paracrine/autocrine effects on reproduction. Various evidences have pointed to a direct role of leptin in the control of rodent testicular function such as steroidogenesis and spermatogenesis. So, detection of leptin and leptin receptor mRNA in bovine testis will be the first crucial step to an understanding of its paracrine/autocrine effect on testes in cattle. In the present study, we showed the expression of leptin mRNA as well as its functional receptor (Ob-Rb) mRNA in whole testis of Holstein cattle using reverse transcription and polymerase chain reaction (RT-PCR) analysis. To confirm the first results, RT-PCR products were amplified with Nested PCR using inner leptin primer pairs designed on different exons. Based on our results, although we could not determine the exact cell source of leptin in testis, it suggests that besides its primary actions at the hypothalamic-pituitary level, leptin can also involved in autocrine and/or paracrine mechanisms in testicular physiology in cattle.

There is little investigation performed regarding the use of metabotropic glutamate receptors in birds. In this study, we had investigated the use of metabotropic glutamate receptor agonist and antagonist to determine the appetite of broiler cockerels.

12 broiler cockerels of were reared until 700-750 grams were bred up. Each was steriotaxically implanted into the right lateral ventricle.Then, the birds were injected with DHPG(1µM) and AIDA(2mM) and cumulative food intake was monitored at different times post injection with computerized program. The birds were given the mentioned food in a replicated latin square design on the 1st, 3rd, 5th and 7th days in 4 groups.

In comparison with the control group, the intracerebroventricular administration of DHPG increased significantly (average 28.7 percent), food intake and AIDA had decreased (average 30 percent) significantly (P<0.05).

According to these results it can be concluded that metabotropic glutamate receptors can, significantly, affect on the appetite of broiler cockerels to intake food.