Does vagotomy reveal the importance of the imidazoline receptors in the cardiovascular effects of marsanidine and 7-ME-marsanidine in rats?
The results show that although cardiovascular effects of marsanidine and 7-Me-marsanidine are not mediated by the vagal nerves, vagotomy enhanced sensitivity of the sympathetic pathways for the tested compounds. While the action of marsanidine in vagotomised and intact rats may be explained by activation of the α2 adrenoreceptors, the effects of 7-Me-marsanidine seem to be α2 adrenoreceptor-independent. It seems likely that activation of I1 imidazoline receptors could mediate the observed effects.
These data confirm the expression of CB1 and CB2 receptors by human islets and indicate that both receptor subtypes are coupled to the stimulation of insulin secretion. They also implicate involvement of CB1/2 receptor-independent pathways in the antagonist-induced stimulatory effects.