Neuropeptide Y in the central nucleus of amygdala regulates the anxiolytic effect of agmatine in rats.
In the present study, modulation of anxiolytic action of agmatine by neuropeptide Y (NPY) in the central nucleus of amygdala (CeA) is evaluated employing Vogel's conflict test (VCT) in rats. The intra-CeA administration of agmatine (0.6 and 1.2µmol/rat), NPY (10 and 20pmol/rat) or NPY Y1/Y5 receptors agonist [Leu(31), Pro(34)]-NPY (30 and 60pmol/rat) significantly increased the number of punished drinking licks following 15min of treatment. Combination treatment of subeffective dose of NPY (5pmol/rat) or [Leu(31), Pro(34)]-NPY (15pmol/rat) and agmatine (0.3µmol/rat) produced synergistic anxiolytic-like effect. However, intra-CeA administration of selective NPY Y1 receptor antagonist, BIBP3226 (0.25 and 0.5mmol/rat) produced anxiogenic effect. In separate set of experiment, pretreatment with BIBP3226 (0.12mmol/rat) reversed the anxiolytic effect of agmatine (0.6µmol/rat). Furthermore, we evaluated the effect of intraperitoneal injection of agmatine (40mg/kg) on NPY-immunoreactivity in the nucleus accumbens shell (AcbSh), lateral part of bed nucleus of stria terminalis (BNSTl) and CeA. While agmatine treatment significantly decreased the fibers density in BNSTl, increase was noticed in AcbSh. In addition, agmatine reduced NPY-immunoreactive cells in the AcbSh and CeA. Immunohistochemical data suggest the enhanced transmission of NPY from the AcbSh and CeA. Taken together, this study suggests that agmatine produced anxiolytic effect which might be regulated via modulation of NPYergic system particularly in the CeA.
Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur (M.S.) 441002, India.
Brijesh G
BG
Taksande
Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur (M.S.) 441002, India.
Nandkishor R
NR
Kotagale
Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur (M.S.) 441002, India.
Dinesh Y
DY
Gawande
Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India.
Ashish P
AP
Bharne
Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur (M.S.) 441002, India.
Chandrabhan T
CT
Chopde
Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India. Electronic address: kokaredada@yahoo.com.
Dadasaheb M
DM
Kokare
D000376:Agmatine / Q000494:pharmacology*; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001007:Anxiety / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D002452:Cell Count; D066274:Central Amygdaloid Nucleus / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D007150:Immunohistochemistry; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009478:Neuropeptide Y / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D009483:Neuropsychological Tests; D009714:Nucleus Accumbens / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D010784:Photomicrography; D017207:Rats, Sprague-Dawley; D017476:Receptors, Neuropeptide Y / Q000037:antagonists & inhibitors / Q000378:metabolism; D012686:Septal Nuclei / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology
D014151:Anti-Anxiety Agents; C092926:BIBP 3226; D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor; C100568:neuropeptide Y5 receptor; C062259:neuropeptide Y, Leu(31)-Pro(34)-; D000376:Agmatine; D001120:Arginine
Agmatine; Anxiety; Central nucleus of amygdala; Neuropeptide Y; Vogel's conflict test