Particle aggregates in plasma and intracellular membranes of toad bladder (granular cell)

Humbert, F; Montesano, Roberto; Grosso, A.; Sousa, R. C. de; Orci, Lelio

doi:10.1007/bf01920184

Cited by 76 publications

(27 citation statements)

References 19 publications

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“…Interestingly, the i.m.p. aggregrates found in intra-cytoplasmic structures of the granular cells of toad bladder (Humbert et al 1977;Wade, 1978) have not been reported, so far, in toad skin. Regardless of the nature of the mechanism leading to the appearance of i.m.p.…”

Section: -9+10-2mentioning

confidence: 92%

“…Such units (water channels or pores) are probably embedded in a structure revealed by the freeze-fracture technique as intramembrane particle (i.m.p.) aggregates (Chevalier, Bourguet & Hugon, 1974;Kachadorian, Wade & DiScala, 1975;Humbert, Montesano, Grosso, De Sousa & Orci, 1977;Wade, 1978). Similar aggregates were recently reported in toad skins exposed either to vasopressin or to isoprenaline (Brown, Grosso & De Sousa, 1979.…”

Section: -9+10-2mentioning

confidence: 99%

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Osmotic water flow across the abdominal skin of the toad Bufo marinus: effect of vasopressin and isoprenaline

Sousa

Grosso

1982

The Journal of Physiology

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4. Methohexital and propranolol selectively inhibited the hydrosmotic effects of vasopressin and isoprenaline, respectively, whereas amiloride and ouabain had no effect.5. Mutual inhibition was found between vasopressin and isoprenaline in skins very sensitive to vasopressin. In less sensitive skins isoprenaline further increased Jw despite exposure of the epithelia to supramaximal concentrations of vasopressin. 6. Differential reactivity to vasopressin was found between the skin and the bladder taken from the same toad. In some instances, the bladder responded normally to vasopressin while the skin was totally unresponsive, suggesting the presence of osmoregulatory mechanisms exerting a local modulation of the vasopressin action in different target epithelia of the same animal.

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Section: -9+10-2mentioning

confidence: 92%

Section: -9+10-2mentioning

confidence: 99%

Osmotic water flow across the abdominal skin of the toad Bufo marinus: effect of vasopressin and isoprenaline

Sousa

Grosso

1982

The Journal of Physiology

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“…Using freeze-fracture electron microscopy, Chevalier et al (22) identified large clusters of particles, arranged in characteristic arrays (linear parallel grooves), which appeared in the apical plasma membrane of ADH-responsive cells during hormonal stimulation. The number of these so-called "particle aggregates" in the membrane was subsequently shown to correlate with the increase in water permeability of the epithelium under most circumstances (93,109). In summary, these and subsequent studies in amphibian tissues revealed 1) that membrane turnover was dramatically increased in response to antidiuretic hormone, 2) cytoskeletal inhibitors markedly inhibited the water permeability response to vasopressin, 3) the intramembrane particle clusters or aggregates were found in intracellular structures in the absence of vasopressin stimulation and could be found in so-called fusion structures after vasopressin stimulation, and 4) membrane capacitance measurements revealed an increase in apical plasma membrane area in response to vasopressin stimulation.…”

Section: A Acute Regulation Of Collecting Duct Water Permeability: Rmentioning

confidence: 99%

Aquaporins in the Kidney: From Molecules to Medicine

Nielsen

Frøkiær

Marples

et al. 2002

Physiological Reviews

1,131

1,022

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The discovery of aquaporin-1 (AQP1) answered the long-standing biophysical question of how water specifically crosses biological membranes. In the kidney, at least seven aquaporins are expressed at distinct sites. AQP1 is extremely abundant in the proximal tubule and descending thin limb and is essential for urinary concentration. AQP2 is exclusively expressed in the principal cells of the connecting tubule and collecting duct and is the predominant vasopressin-regulated water channel. AQP3 and AQP4 are both present in the basolateral plasma membrane of collecting duct principal cells and represent exit pathways for water reabsorbed apically via AQP2. Studies in patients and transgenic mice have demonstrated that both AQP2 and AQP3 are essential for urinary concentration. Three additional aquaporins are present in the kidney. AQP6 is present in intracellular vesicles in collecting duct intercalated cells, and AQP8 is present intracellularly at low abundance in proximal tubules and collecting duct principal cells, but the physiological function of these two channels remains undefined. AQP7 is abundant in the brush border of proximal tubule cells and is likely to be involved in proximal tubule water reabsorption. Body water balance is tightly regulated by vasopressin, and multiple studies now have underscored the essential roles of AQP2 in this. Vasopressin regulates acutely the water permeability of the kidney collecting duct by trafficking of AQP2 from intracellular vesicles to the apical plasma membrane. The long-term adaptational changes in body water balance are controlled in part by regulated changes in AQP2 and AQP3 expression levels. Lack of functional AQP2 is seen in primary forms of diabetes insipidus, and reduced expression and targeting are seen in several diseases associated with urinary concentrating defects such as acquired nephrogenic diabetes insipidus, postobstructive polyuria, as well as acute and chronic renal failure. In contrast, in conditions with water retention such as severe congestive heart failure, pregnancy, and syndrome of inappropriate antidiuretic hormone secretion, both AQP2 expression levels and apical plasma membrane targetting are increased, suggesting a role for AQP2 in the development of water retention. Continued analysis of the aquaporins is providing detailed molecular insight into the fundamental physiology and pathophysiology of water balance and water balance disorders.

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“…The binding of ADH to receptors on the basolateral surface of this epithelium produces a large increase in water permeability of the granular cell apical membrane as well as increases in urea permeability and active sodium transport (1). ADH increases the granular cell content of cyclic AMP (2) which, through a series of unknown steps, causes the fusion of unique tubular-shaped cytoplasmic vesicles (termed aggrephores) with the apical plasma membrane (3)(4)(5). Distinctive intramembrane particle aggregates visualized by freeze-fracture electron microscopy (6,7), are contained within the aggrephore-limiting membrane.…”

Section: Introductionmentioning

confidence: 99%

Transepithelial water flow regulates apical membrane retrieval in antidiuretic hormone-stimulated toad urinary bladder.

Harris¹,

Wade²,

Handler³

1986

J. Clin. Invest.

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Antidiuretic hormone (ADH) increases the osmotic water permeability (P...) oftoad urinary bladder. This increase is believed to be produced by fusion of intracellular vesicles called aggrephores with the granular cell apical plasma membrane. Aggrephores contain intramembrane particle aggregates postulated to be water channels. ADH-stimulated P.3 is decreased by osmotic gradient exposure, which is termed flux inhibition. We studied flux inhibition by exposing ADH-stimulated bladders to various osmotic gradients. Osmotic water flow was initially proportional to the applied osmotic gradient, but P.., decreased with time. Ultrastructural and quantitative studies of endocytosis demonstrate that apical membrane retrieval was a direct function of the transepithelial osmotic gradient. PO. remained unchanged when apical membrane retrieval was blocked by incubation of bladders at 20C, or under low water-flow conditions. These effects were reversed by increases in temperature or the applied osmotic gradient. We conclude that apical membrane retrieval causes the phenomenon of flux inhibition.

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Particle aggregates in plasma and intracellular membranes of toad bladder (granular cell)

Cited by 76 publications

References 19 publications

Osmotic water flow across the abdominal skin of the toad Bufo marinus: effect of vasopressin and isoprenaline

Osmotic water flow across the abdominal skin of the toad Bufo marinus: effect of vasopressin and isoprenaline

Aquaporins in the Kidney: From Molecules to Medicine

Transepithelial water flow regulates apical membrane retrieval in antidiuretic hormone-stimulated toad urinary bladder.

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