title: Distribution and content of microtubules in relation to the transport of lipid. An ultrastructural quantitative study of the absorptive cell of the small intestine.
abstract: To determine whether microtubules are linked to intracellular transport in absorptive cells of the proximal intestine, quantitative ultrastructural studies were carried out in which microtubule distribution and content were determined in cells from fasting and fed animals. Rats were given a 1-h meal of standard chow, and tissue was taken from the mid-jejunum before, 1/2 h, and 6 h after the meal. The microtubule content of apical, Golgi, and basal regions of cells was quantitated by point-counting stereology. The results show) that microtubules are localized in intracellular regions of enterocytes (apical and Golgi areas) previously shown to be associated with lipid transport, and that the microtubule content within apical and Golgi regions is significantly (P less than 0.01) reduced during transport of foodstuffs. To determine the effect of inhibition of microtubule assembly on transport, colchicine or vinblastine sulfate was administered to postabsorptive rats, and the lipid and microtubule content of enterocytes determined 1 and 3 h later. After treatment with these agents, lipid was found to accumulate in apical regions of the cells; this event was associated with a significant reduction in microtubule content. In conclusion, the regional distribution of microtubules in enterocytes, the decrease in assembled microtubules after a fat-containing meal, and the accumulation of lipid after the administration of antimicrotubule agents suggest that microtubules are related to lipid transport in enterocytes.
mesh_terms: D000818:Animals; D004041:Dietary Fats; D005260:Female; D007408:Intestinal Absorption; D007421:Intestine, Small / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D050356:Lipid Metabolism; D008854:Microscopy, Electron; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004041:Dietary Fats
references.citation: J Biol Chem. 1962 May;237:1454-9
references.pmid: 13910673
references.citation: J Biophys Biochem Cytol. 1959 May 25;5(3):373-84
references.pmid: 13664677
references.citation: Recent Prog Horm Res. 1973;29:199-228
references.pmid: 4584365
references.citation: Biochim Biophys Acta. 1973 Apr 13;306(1):142-7
references.pmid: 4350003
references.citation: J Clin Invest. 1974 Aug;54(2):326-38
references.pmid: 4211161
references.citation: Recent Prog Horm Res. 1973;29:229-85
references.pmid: 4584367
references.citation: J Cell Biol. 1974 Aug;62(2):390-405
references.pmid: 4426914
references.citation: J Clin Invest. 1974 Jun;53(6):1512-7
references.pmid: 4830218
references.citation: Fed Proc. 1974 Feb;33(2):158-66
references.pmid: 4855812
references.citation: Int Rev Cytol. 1969;26:235-302
references.pmid: 4899604
references.citation: Ann N Y Acad Sci. 1975 Jun 30;253:723-37
references.pmid: 1096729
references.citation: Ann N Y Acad Sci. 1975 Jun 30;253:653-69
references.pmid: 1096726
references.citation: Science. 1976 Jan 9;191(4222):88-90
references.pmid: 1108194
references.citation: J Clin Invest. 1975 Jul;56(1):49-55
references.pmid: 1141440
references.citation: Am J Vet Res. 1975 Aug;36(08):1153-66
references.pmid: 1171646
references.citation: J Lipid Res. 1971 Sep;12(5):580-9
references.pmid: 5098394
references.citation: J Cell Biol. 1967 Jul;34(1):123-55
references.pmid: 6033529