In vivo adaptative regulation of muscarinic receptors and muscarinic stimulation-induced Ca2+ mobilization during short-term heat exposure in rat parotid glands

Fujinami, Hiroyuki; Komabayashi, K.; Izawa, Tetsuya; Suda, Kazuhiro; Tsuboi, Masahiro

doi:10.1016/0742-8413(93)90085-y

Cited by 2 publications

(2 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ished IP 3 production and decreased release of calcium from the endoplasmic stores. Several steps in this cascade were reported by Fujinami et al (9) in the parotid gland.…”

Section: Discussionmentioning

confidence: 68%

“…An altered ratio of low-affinity to high-affinity MR subtype populations was also observed together with changes in the magnitude of the calcium signal evoked by supramaximal concentrations of carbamylcholine (CCh). Under similar conditions, in the rat parotid, Fujinami et al (7)(8)(9) reported an array of transient cellular responses involving the upregulation of MR, coincident with the reduced generation of inositol-1,4,5-trisphosphate (IP 3 ), a second messenger in the MR transduction cascade, and a drop in Ca 2ϩ mobilization in response to IP 3 administration. This was followed by a decrease in carbachol-stimulated IP 3 generation and CCh-evoked calcium concentration signal ([Ca 2ϩ ] s ) amplitude.…”

mentioning

confidence: 94%

See 1 more Smart Citation

Heat acclimation and heat stress have different effects on cholinergic-induced calcium mobilization

Kaspler

Horowitz

2001

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

There is evidence that the signal transduction array responsible for the secretion of water in evaporative cooling by the submaxillary gland of the rat is subject to heat acclimatory responses. The objectives of the present study were 1) to examine whether heat acclimation affects intracellular Ca(2+) mobilization and, in turn, submaxillary glandular responsiveness; 2) to assess whether the acclimatory responses differ from those evoked on heat stress (HS). Experiments were conducted on submaxillary glands of rats acclimated at 34 degrees C for 0, 2 [short-term heat acclimation (STHA)], and 30 [long-term heat acclimation (LTHA)] days. The resting cytosolic calcium concentration ([Ca(2+)](c)) and the carbamylcholine-evoked calcium signal ([Ca(2+)](s)) of dispersed glandular cells were measured using the fluorescent dye fura 2 AM. Inositol-1,4,5-trisphosphate (IP(3))-sensitive endoplasmic reticulum Ca(2+) stores were determined in permeabilized cells using fura 2 potassium salt. STHA resulted in a drop in both [Ca(2+)](s) and IP(3)-sensitive Ca(2+) stores. On LTHA, the [Ca(2+)](s) amplitude reverted to the preacclimation value, whereas the IP(3)-sensitive Ca(2+) stores remained low. The drop in [Ca(2+)](s) on STHA is in accord with the decreased glandular output (measured by (86)Rb efflux) observed during this acclimation phase. However, after LTHA the enhanced glandular output despite reduced [Ca(2+)](s) levels suggests an increased efficiency of cellular secretory mechanisms in that group. Collectively, the alterations in [Ca(2+)](s) support our biphasic acclimation model (Horowitz M, Kaspler P, Marmari Y, and Oron Y. J Appl Physiol 80: 77--85, 1996.). In nonacclimated glands, HS caused an elevation in [Ca(2+)](s) coincidentally with a decrease in the IP(3) Ca(2+) stores. In contrast, [Ca(2+)](s) in both STHA and LTHA glands was not affected by HS, despite a marked increase in the IP(3)-sensitive Ca(2+) stores in the LTHA glands. The opposing responses to HS and heat acclimation in calcium signaling and stores confirm the specificity of each process.

show abstract

“…ished IP 3 production and decreased release of calcium from the endoplasmic stores. Several steps in this cascade were reported by Fujinami et al (9) in the parotid gland.…”

Section: Discussionmentioning

confidence: 68%

mentioning

confidence: 94%

Heat acclimation and heat stress have different effects on cholinergic-induced calcium mobilization

Kaspler

Horowitz

2001

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

show abstract

Do Cellular Heat Acclimation Responses Modulate Central Thermoregulatory Activity?

Horowitz

1998

Physiology

View full text Add to dashboard Cite

The classical concept of heat acclimation is of an autonomically controlled array of integrative physiological processes, improving heat tolerance. New evidence suggests that a temporal interplay between opposing autonomic and peripheral cell-originated responses, switched on by heat and autonomic stimulation of the cell membrane, and a marked increase in the stock of the inducible 70-kDa heat shock protein contribute to widening of the thermoregulatory activity span.

show abstract

In vivo adaptative regulation of muscarinic receptors and muscarinic stimulation-induced Ca2+ mobilization during short-term heat exposure in rat parotid glands

Cited by 2 publications

References 23 publications

Heat acclimation and heat stress have different effects on cholinergic-induced calcium mobilization

Heat acclimation and heat stress have different effects on cholinergic-induced calcium mobilization

Do Cellular Heat Acclimation Responses Modulate Central Thermoregulatory Activity?

Contact Info

Product

Resources

About