Lesions of the lateral hypothalamus impair the pressor response to clonidine injected into the medial septal area of conscious rats
Rev. bras. pesqui. méd. biol
; Braz. j. med. biol. res;25(8): 857-60, 1992. ilus
Article
em En
| LILACS
| ID: lil-113583
Biblioteca responsável:
BR26.1
ABSTRACT
The central injection of clonidine (an alpha2-adrenoceptor agonist) in conscious normotensive rats produces hypertensive responses and breadycardia. The present study performed was performed to investigate the effect of electrolytic lesions of the lateral hypothalamus (LH) on the pressor and bradycardiac responses induced by clonidine injected into the medial septal area (MSA) in conscious and unrestrained rats. Male Holtzman rats weighing 250-300 g were used. Mean arterial pressure and heart rate were recorded in sham- or bilateral LH-lesioned rats with a cerebral stainless steel cannula implanted into the MSA. The injection of clonidine (40 nmol/ul) into the MSDA of sham rats (N=8) produced a pressor response (36 ñ 7 mmHg, P<0.05) and bradycardia (-70 ñ 13 bpmm, P<0.05) compared to saline. Fourteen days after LH-lesion (N=9) the pressor response was reduced (9 ñ 10 mmHg, P<0.05) but no change was observed in the bradycardia (-107 ñ 24 bpm). These results show that LH is an important area involved in the pressor response to clonidine injected into the MSA of rats
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Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
Bradicardia
/
Receptores Adrenérgicos
/
Clonidina
/
Pressão Arterial
/
Frequência Cardíaca
/
Hipotálamo
Limite:
Animals
Idioma:
En
Revista:
Braz. j. med. biol. res
/
Rev. bras. pesqui. méd. biol
Assunto da revista:
BIOLOGIA
/
MEDICINA
Ano de publicação:
1992
Tipo de documento:
Article
País de publicação:
Brasil