Skeletal muscle microcirculatory response to rat alpha-calcitonin gene-related peptide.

We used in vivo video microscopy to determine the effect of increasing doses of rat alpha-calcitonin gene-related peptide (rCGRP) on rat cremaster muscle arterioles in the presence or absence of the nitric oxide synthase inhibitor N-omega-nitro-L-arginine (L-NNA). Male Sprague-Dawley rats (118-148 g) were anaesthetized with pentobarbital, and neurovascularly intact cremaster muscles were imaged. Changes in the diameter, erythrocyte velocity and volume flow in second-(A2), third-(A3), and fourth-(A4) order arterioles were determined.

Small intestinal microcirculatory effects of octreotide.

Somatostatin and its analogue, octreotide acetate, are thought to decrease mesenteric blood flow; however, it is unknown whether the decrease occurs at the central, regional, or microvascular level. We hypothesized that the circulatory effects of octreotide are regulated at the microvascular level. Changes in superior mesentery artery (SMA) flow in response to octreotide were measured with a perivascular ultrasonic flow probe.