The Carotid Labyrinth of Rana tigrina

Parathyroid Gland of the Frog Rana Tigrina

The parathyroid gland of Rana tigrina is composed of closely packed epithelial cells which are arranged in whorls. A difference in the density of the parathyroída1 cells has been noticed. Cells in the center of the gland are packed compactly possessing elongated nuclei and denser cytoplasm. The cells at periphery of the gland are loosely arrenged having lightly stained cytoplasm and large spher...

Action of magnesium sulphate on melanophores of Rana tigrina.

20% MgSO. (1 mlll00 gm weight) was injected and the frogs were observed. IS-20 minuteslater it was seen that there was a marked depression of the CNS which was manifested in a loss of the righting reflex. At this time there was an obvious change in the colour of the 'Paper presented at the xm Annual Conference of the Association of Physiologists and Pharmacologists of Indiaheld at Pondicherry i...

Tissue catecholamines in Rana tigrina and effects of reserpine.

Reserpine depletes tissue catecholamine contents (CAs) in mammals (1, 2) but may (3, 4, 5) or may not (6) affect the CA stores of cold-blooded animals such as the turtle, frog and toad. Doses as high as 50 mg/kg for 3 days failed to decrease toad tissue CAs (6), which were, however, reported to be sensitive to much lower doses if the ambient temperature was high (7). However, no reference to th...

Peptidergic innervation in the amphibian carotid labyrinth.

The amphibian carotid labyrinth, which corresponds to the mammalian carotid body and carotid sinus, is innervated by nerve fibers containing substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), FMRFamide (FMRF), and somatostatin (SOM). SP, CGRP, VIP, and NPY immunoreactive varicose fibers are more densely distributed in the per...

The Action of Nicotinic Acid on the Heart of Rana Tigrina