[Microinjection of 5-HT into the rostral ventrolateral medulla reduced the hyperviscosity and elevation of blood pressure induced by stress].
Experiments were carried out on 62 wistar rats. The hyperviscosity and elevation of blood pressure were induced by hanging and restraining the rats with their four limbs tied on a frame. It was found that microinjection of 5-HT (25 micrograms/10 microliters) into the 4th ventricle of the brain or bilateral microinjection of 5-HT (4 micrograms/0.5 microliters/site) into rostral ventrolateral medulla (rVLM) reduced stress-induced hyperviscosity (p < 0.01) and elevation of blood pressure (p < 0.01). The effect of 5-HT injected into the 4th ventricle or rVLM was blocked by bilateral microinjection of cinanserine (4 micrograms/0.5 microliter/site) into rVLM. These results suggest that microinjection of 5-HT into 4th ventricle and rVLM could reduce stress-induced hyperviscosity and elevation of blood pressure and these effects were probably mediated via 5-HT receptors in the rVLM.
Weng
K
K
Department of Physiology, Shanghai Medical University.
Guo
X O
XO
Liang
Z J
ZJ
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001809:Blood Viscosity / Q000187:drug effects; D007276:Injections, Intraventricular; D008297:Male; D008526:Medulla Oblongata / Q000502:physiology*; D008845:Microinjections; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology*; D013312:Stress, Physiological / Q000503:physiopathology*
D011985:Receptors, Serotonin; D012701:Serotonin