Pressor Effect of Intracerebroventricular Diphenhydramine and Ranitidine in Rabbits.
- Author:
Han Ho CHO
;
Soo Han KIM
;
Sam Suk KANG
;
Je Hyuk LEE
;
Jung Hyun WOO
- Publication Type:Original Article
- Keywords:
Antihistamines;
Diphenhydramine;
Ranitidine;
Intracerebroventricle;
H1-receptor H2-receptor
- MeSH:
Blood Pressure;
Diphenhydramine*;
Histamine Antagonists;
Rabbits*;
Ranitidine*
- From:Journal of Korean Neurosurgical Society
1991;20(10-11):905-910
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
This study was undertaken to observe the effects of centrally administred antihistamines on the blood pressure. Diphenhydramine(DPH), a H1-receptor antagonist, and ranitidine(RAN), a H2-receptor antagonist were administered intracerebroventricularly(icv) on urethane-anesthetized rabbits. 1) Both DPH and RAN administered intraccebroventricularly increased blood pressure, however the intravenous(iv) adminstration of them did not affect blood pressure. The pressor response to icv DPH was dose-dependent, but that to icv RAN was not. 2) The pressor response to icv DPH(1mg) was either markedly attenuated or reversed to depressor response by the pretreatment with icv phentolamine(250,500ug), and iv chlorisondamine(0.1, 1mg/Kg) and iv phenoxybenzamine(1mg/Kg). In cord-sectioned rabbtis, icv RAN) 1mg) did not produce pressor response. 3) The pressor responsr to icv RAN(1mg) was not affected by the pretreatment with icv phentolamine(500ug), iv chlorisondamin(1mg/Kg) and iv phenoxybenzamine(1mg/Kg), and iv phenoxybenzamine(1mg/Kg). RAN also producted pressor response in cordsectioned rabbits. These results suggest that the pressor response to icv DPH is elecited by increasing peripheral sympathetic tone via the stimulation of central alpha-adrenoreceptors and the pressor response to icv RAN is produced by releasing some humoral facotr which can increase blood pressure.
