Abstract:
:Experiments were done for indentification and localization of certain structural changes at different levels of jejunal villus of the hamster during positive and negative water transport across the intestine in vivo and in vitro. Positive transport occurred when the mucosal surface of the intestine was bathed (in vitro experiments) or perfused (in vivo experiments) with isotonic Krebs-Ringer bicarbonate solution containing 10 mM glucose, and negative water transport was achieved by rendering this solution hypertonic with 150 mM mannitol. Results indicate that during positive net water transport the intestine in vivo transported more fluid and exhibited a more conspicuous dilatation of the lateral intercellular spaces (L.I.S.) than did the in vitro preparation. Dilatation of the L.I.S. in both preparations was present only in the apical part of the villus, suggesting that this is the principal site of water absorption. When the mucosal solution was made hypertonic with mannitol, the L.I.S. in the in vivo intestine totally collapsed, whereas in the in vitro intestine these spaces remained open very slightly. These morphological changes correspond well with our finding that in the presence of the hypertonic mucosal solution there was a greater net negative water transport in vivo than in vitro. Incubation of the intestine in the isotonic mucosal solution produced subnuclear swelling of the mid-villus epithelial cells, and this morphological change was associated with an increase in the water content of the tissue. Perfusion of the in vivo intestine with the isotonic solution produced neither the swellings nor the increase in water content of the tissue. In the presence of hypertonic mucosal solution there was a water loss from the tissue both in vivo and in vitro, and these swellings were not observed. These results are discussed in relation to intestinal sugar transport and to the maturity of the epithelial cells, and it is concluded that transport studies on in vitro preparations may provide valid information on a qualitative basis, if not on a strictly quantitative basis.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Melligott TF,Beck IT,Dinda PK,Thompson Sdoi
10.1139/y75-063subject
Has Abstractpub_date
1975-06-01 00:00:00pages
439-50issue
3eissn
0008-4212issn
1205-7541journal_volume
53pub_type
杂志文章abstract::A variety of neural factors can influence reproductive hormone secretion by neuromodulatory actions within the hypothalamus or neuroendocrine actions within the anterior pituitary gland. Passive immunoneutralization and antagonist administration protocols have suggested physiological roles for a number of these factor...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-102
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
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更新日期:2012-06-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
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doi:
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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更新日期:1989-04-01 00:00:00
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pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-105
更新日期:1990-06-01 00:00:00
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更新日期:2002-07-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2006-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1980-03-01 00:00:00
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更新日期:2005-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1996-06-01 00:00:00
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pub_type: 杂志文章
doi:10.1139/y77-003
更新日期:1977-02-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-012
更新日期:1982-01-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-76-7-8-707
更新日期:1998-07-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1993-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1995-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:2002-04-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y93-041
更新日期:1993-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
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更新日期:1998-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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更新日期:1980-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
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更新日期:1995-07-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
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