当前位置： SCI文献检索 > BRITISH JOURNAL OF PHARMACOLOGY期刊下所有文献 > The role of alpha- and beta-adrenoceptor subtypes in mediating the effects of catecholamines on fasting glucose and insulin concentrations in the rat.

The role of alpha- and beta-adrenoceptor subtypes in mediating the effects of catecholamines on fasting glucose and insulin concentrations in the rat.

Abstract：

:1. The role of alpha- and beta-adrenoceptor subtypes in the regulation of plasma glucose and immunoreactive insulin (IRI) levels has been investigated in normal conscious fasted rats by employing selective agonists and antagonists. 2. Adrenaline (0.2 mg kg-1)-induced hyperglycaemia was abolished by the selective alpha 2-adrenoceptor antagonist idazoxan (1.0 mg kg-1), unaltered by non-selective beta-adrenoceptor blockade (propranolol, 1.0 mg kg-1) and potentiated by the selective alpha 1-adrenoceptor antagonist prazosin (0.3 mg kg-1). Adrenaline increased plasma IRI levels in the presence of idazoxan but not in the presence of either prazosin or propranolol. 3. The selective alpha 2-adrenoceptor agonists UK 14304 (0.1 and 0.3 mg kg-1) and BHT-920 (0.2 and 0.5 mg kg-1) elicited dose-dependent hyperglycaemic responses, but did not alter plasma IRI levels. UK 14304 (0.1 mg kg-1)-evoked hyperglycaemia was blocked by idazoxan but not by prazosin. 4. The selective alpha 1-adrenoceptor agonists methoxamine (0.3 mg kg-1) and phenylephrine (0.3 mg kg-1) failed to modify either plasma glucose or IRI levels. 5. Isoprenaline (0.2 mg kg-1) elicited hyperglycaemic and insulinotropic responses which were attenuated by propranolol (1.0 mg kg-1) and the selective beta 2-adrenoceptor antagonist ICI 118551 (1.0 mg kg-1), but not by the beta 1-selective antagonists atenolol (1.0 mg kg-1) and betaxolol (1.0 mg kg-1). 6. None of the antagonists per se affected basal plasma glucose or IRI concentrations, except prazosin (1.0 mg kg-1). 7. The results indicate that adrenoceptors do not appear to be involved in regulating basal plasma glucose and IRI concentrations in the fasted rat. However, the effects of catecholamines on these parameters are mediated by alpha 2- and beta 2-adrenoceptors, whereas alpha,- or beta l-adrenoceptors do not appear to be involved.

journal_name

Br J Pharmacol

journal_title

British journal of pharmacology

authors

John GW,Doxey JC,Walter DS,Reid JL

doi

10.1111/j.1476-5381.1990.tb14078.x

subject

Has Abstract

pub_date

1990-08-01 00:00:00

pages

699-704

issue

eissn

0007-1188

issn

1476-5381

journal_volume

100

pub_type

杂志文章

在线工具

The role of alpha- and beta-adrenoceptor subtypes in mediating the effects of catecholamines on fasting glucose and insulin concentrations in the rat.