Cardiovascular effects of intracerebral injection of neuropeptide Y in rats
Yang, S.N.; Yang, W.; Tang, Y.H.; Wang, S.
Zhongguo Yao Li Xue Bao 13(2): 116-118
1992
ISSN/ISBN: 0253-9756 PMID: 1598826 Document Number: 389358
Cardiovascular effects of microinjection of neuropeptide Y (NPY) (25, 50, and 100 pmol/site) into field CA3 of hippocampus (CA3), lateral septal nuclei (LSN) and substantia nigra (SN) were investigated in urethane-anesthetized rats. NPY administered into CA3 produced a dose-dependent hypotension and bradycardia. Maximal changes of mean arterial blood pressure (MAP) were -1.5 .+-. 0.7, -2.0 .+-. 0.4, and -4.2 .+-. 1.6 kPa, respectively; maximal changes of heart rate (HR) were -7 .+-. 14, -23 .+-. 24, and -64 .+-. 50 bpm, respectively. NPY microinjection into LSN produced a dose-dependent increase in MAP (0.9 .+-. 0.8, 1.3 .+-. 0.5, and 3.1 .+-. 0.5 kPa, respectively) and a prominent increase in HR (14 .+-. 15, 41 .+-. 28, and 42 .+-. 31 bpm, respectively), but the tachycardia was not dose-dependent. NPY applied into SN elicited a dose-dependent decrease in MAP (-1.0 .+-. 0.5, -2.2 .+-. 0.9, and -4.3 .+-. 2.0 kPa, respectively), but no statistically significant change in HR. The results showed that exogenously applied NPY has distinct cardiovascular effects in CA3, LSN, and SN.