Sexual dimorphism in forelimb muscles of the bullfrog, Rana catesbeiana: a functional analysis of isometric contractile properties.

Isometric contractile properties of sexually dimorphic forelimb muscles in the marine toad Bufo marinus Linnaeus 1758: functional analysis and implications for amplexus.

It has been shown in the bullfrog, Rana catesbeiana Shaw 1802, that certain forelimb muscles in males have different contractile properties when compared with females, which may result from adaptation for amplexus. We extended this study to a distantly related species, Bufo marinus Linnaeus 1758, by testing the isometric contractile properties of three muscles, abductor indicus longus (AIL), an...

Effects of testosterone on contractile properties of sexually dimorphic forelimb muscles in male bullfrogs (Rana catesbeiana, Shaw 1802)

This study examined the effects of testosterone (T) on the contractile properties of two sexually dimorphic forelimb muscles and one non-dimorphic muscle in male bullfrogs (Rana catesbeiana, Shaw 1802). The dimorphic muscles in castrated males with testosterone replacement (T+) achieved higher forces and lower fatigability than did castrated males without replaced testosterone (T0 males), but t...

Sexual dimorphism of extensor carpi radialis muscle size, isometric force, relaxation rate and stamina during the breeding season of the frog Rana temporaria Linnaeus 1758.

Mating success of individual male frogs within explosive breeding species can depend on their ability to compete for a mate and to hold onto that mate during amplexus. Such importance of amplexus has resulted in the evolution of sexual dimorphism in the morphology and contractile characteristics of the anuran forelimb muscles used during amplexus. The aims of our study were to use an explosive ...

Time-Resolved 31P-NMR Studies on Contraction and Recovery o f Bullfrog Sartorius Muscles

Ghrelin Receptor in Two Species of Anuran Amphibian, Bullfrog (Rana catesbeiana), and Japanese Tree Frog (Hyla japonica)

We have identified cDNA encoding a functional growth hormone secretagogue-receptor 1a (GHS-R1a, ghrelin receptor) in two species of anuran amphibian, the bullfrog (Rana catesbeiana), and the Japanese tree frog (Hyla japonica). Deduced receptor protein for bullfrog and Japanese tree frog (tree frog) was comprised of 374- and 371-amino acids, respectively. The two receptors shared 86% identity, a...