1. KCl-induced depolarization resulted in a large stimulation of the 45Ca efflux from both cockroach skeletal muscle and rat ileal smooth muscle. 2. Caffeine (10 mM) induced a large stimulation of 45Ca efflux from skeletal muscle, but a fall in the efflux from ileal muscle, especially if the efflux was previously stimulated by KCl depolarization. 3. Caffeine inhibited calcium uptake by skeletal muscle mitochondria and sarcoplasmic reticulum, was without effect on ileal muscle mitochondria, but significantly increased caclium binding by ileal muscle membrane vesicular preparations. 4. The induction of contractures and stimulation of 45Ca efflux in skeletal muscle by caffeine are clearly related to inhibition of intracellular calcium binding by the sarcoplasmic reticulum and mitochondria. 5. The relaxation of ileal muscle by caffeine and the inhibition of fibre calcium efflux correlate well with caffeine enhancement of intracellular calcium binding. These experiments suggest that the membrane vesicular compartment may be the main agency centrally involved in fibre calcium regulation in this muscle during the contraction-relaxation cycle.
The effect of caffeine on calcium efflux and calcium translocation in skeletal and visceral muscle
H. Huddart, A. J. Syson; The effect of caffeine on calcium efflux and calcium translocation in skeletal and visceral muscle. J Exp Biol 1 August 1975; 63 (1): 131–142. doi: https://doi.org/10.1242/jeb.63.1.131
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New funding schemes for junior faculty staff
In celebration of our 100th anniversary, JEB has launched two new grants to support junior faculty staff working in animal comparative physiology and biomechanics who are within five years of setting up their first lab/research group. Check out our ECR Visiting Fellowships and Research Partnership Kickstart Travel Grants. First deadline for applications is 15 July 2023.
JEB@100: an interview with Monitoring Editor Sanjay Sane
Sanjay Sane tells us about his first experience of publishing with the journal and why he thinks JEB is going to play a key role in our understanding of the current climate crisis and its implications for biodiversity.
The Forest of Biologists
The Forest of Biologists is a biodiversity initiative created by The Company of Biologists, with support from the Woodland Trust. For every Research and Review article published in Journal of Experimental Biology a native tree is planted in a UK forest. In addition to this we are protecting and restoring ancient woodland and are dedicating these trees to our peer reviewers. Visit our virtual forest to learn more.
Celebrating 100 years of discovery
This Special Issue focuses on broad biological questions addressed through the lens of comparative biomechanics. Crosscutting through time, this series of Reviews, Commentaries and Research Articles addresses questions from the vantage points of the history of the field, today’s research, and the future of comparative biomechanics. Read the Editorial by Sheila Patek, Monica Daley and Sanjay Sane.
Centenary Review - Adaptive echolocation behavior
Cynthia F. Moss and colleagues Review the behaviours used by echolocating mammals to track and intercept moving prey, interrogate dynamic sonar scenes, and exploit visual and passive acoustic stimuli.
Crucial DNA at crux of insect wing size evolution
Keity Farfán-Pira and colleagues have revealed that a tiny region of regulatory DNA in the vestigial gene governs whether insect wings are large or small and has played a key role in the evolution of insect wing size.