Abstract
The intracellular transport of sulfated glycosaminoglycans (heparan sulfate and chondroitin sulfate) and glycoproteins of the prolactin (PRL) granule matrix, as well as that of PRL, was studied using a system of double-labeled bovine anterior pituitary slices. [(35)S]sulfate was used to label sulfated macromolecules and L-[(3)H]leucine to label PRL. In membraneless granules (isolated from a PRL granule fraction after solubilization of the membrane with Lubrol PX), sulfated glycosaminoglycans and glycoproteins were considerably labeled after a 15- min pulse, while the hormone was still unlabeled. During the chase incubation, the specific radioactivity of granule PRL and the various complex carbohydrate classes first increased, reaching a peak after approximately 40 min, and then began to decline. After 4 h of chase incubation the radioactivity remaining in granule PRL and sulfated complex carbohydrates was 50-60 percent of that observed at 40 min. Thus, in pituitary mammotrophs a pool of sulfated glycoproteins and glycosaminoglycans is transported intracellularly in parallel with PRL. This finding corroborates the previous conclusion (Zanini et al., 1980 J. Cell. Biol. 86:260-272) that sulfated macromolecules are structural components of the granule matrix. The discharge of labeled PRL and complex carbohydrates from the slices to the incubation medium was also investigated. [(35)S]-glycosaminoglycans and glycoproteins were released at a rapid rate during the first 30-40 min of chase incubation, when PRL granules had not yet attained maximum specific activities. By 40 min, their release tended to level off but the radioactivity accumulating in the incubation medium was still much larger (approximately a fourfold increase) than the losses observed concomitantly in PRL granules. These discharge kinetics contrast with that of [(3)H]PRL, which was not released during the 1st h of chase incubation but then began to accumulate at a high rate in the medium, in parallel with its decrease in granules. Dopamin (5 x 10(-7) M) strongly inhibited the release of labeled PRL but had no detectable effect on the release of labeled glycosaminoglycans and glycoproteins or on the discharge of (35)S-macromolecules as revealed by SDS polyacrylamide gel electrophoresis of incubation media. Thus the releases of PRL and sulfated macromolecules have different kinetics and can be dissociated from each other. These data indicate that much of the flycosaminoglycans and glycoproteins release form pituitary slices originates from sites other than PRL granules, and that at least part of the complex carbohydrates of the PRL granule matrix might not be released with the hormone but rather remains associated with the mammotroph cells after exocytosis.
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- Berg N. B., Austin B. P. Intracellular transport of sulfated macromolecules in parotid acinar cells. Cell Tissue Res. 1976 Jan 26;165(2):215–225. doi: 10.1007/BF00226660. [DOI] [PubMed] [Google Scholar]
- Berg N. B. Sulphate metabolism in the exocrine pancreas. II. The production of sulphated macromolecules by the mouse exocrine pancreas. J Cell Sci. 1978 Jun;31:199–211. doi: 10.1242/jcs.31.1.199. [DOI] [PubMed] [Google Scholar]
- Berg N. B., Young R. W. Sulfate metabolism in pancreatic acinar cells. J Cell Biol. 1971 Aug;50(2):469–483. doi: 10.1083/jcb.50.2.469. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blaschke E., Uvnäs B. Effect of splenic nerve stimulation on the contents of noradrenaline, ATP and sulphomucopolysaccharides in noradrenergic vesicle fractions from the cat spleen. Acta Physiol Scand. 1979 Apr;105(4):496–507. doi: 10.1111/j.1748-1716.1979.tb00114.x. [DOI] [PubMed] [Google Scholar]
- Borgese N., De Camilli P., Tanaka Y., Meldolesi J. Membrane interactions in secretory cell systems. Symp Soc Exp Biol. 1979;33:117–144. [PubMed] [Google Scholar]
- Dacheux F., Dubois M. P. Ultrastructural localization of prolactin, growth hormone and luteinizing hormone by immunocytochemical techniques in the bovine pituitary. Cell Tissue Res. 1976 Oct 29;174(2):245–260. doi: 10.1007/BF00222162. [DOI] [PubMed] [Google Scholar]
- Donoso A. O., Banzán A. M., Barcaglioni J. C. Further evidence on the direct action of L-Dopa on prolactin release. Neuroendocrinology. 1974;15(3-4):236–239. doi: 10.1159/000122312. [DOI] [PubMed] [Google Scholar]
- Farquhar M. G. Recovery of surface membrane in anterior pituitary cells. Variations in traffic detected with anionic and cationic ferritin. J Cell Biol. 1978 Jun;77(3):R35–R42. doi: 10.1083/jcb.77.3.r35. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Farquhar M. G., Reid J. J., Daniell L. W. Intracellular transport and packaging of prolactin: a quantitative electron microscope autoradiographic study of mammotrophs dissociated from rat pituitaries. Endocrinology. 1978 Jan;102(1):296–311. doi: 10.1210/endo-102-1-296. [DOI] [PubMed] [Google Scholar]
- Farquhar M. G. Secretion and crinophagy in prolactin cells. Adv Exp Med Biol. 1977;80:37–94. doi: 10.1007/978-1-4615-6675-5_3. [DOI] [PubMed] [Google Scholar]
- Haddad A., Pelletier G., Marchi F., Brasileiro I. L. Light microscope radioautographic study of glycoprotein secretion in the hypothalamic-neurohypophysial system of the rat, after L-fucose-3H injection. Cell Tissue Res. 1977 Feb 2;177(1):67–79. doi: 10.1007/BF00221119. [DOI] [PubMed] [Google Scholar]
- Hymer W. C., Snyder J., Wilfinger W., Swanson N., Davis J. A. Separation of pituitary mammotrophs from the female rat by velocity sedimentation at unit gravity. Endocrinology. 1974 Jul;95(1):107–122. doi: 10.1210/endo-95-1-107. [DOI] [PubMed] [Google Scholar]
- Kronquist K. E., Elmahdy A., Ronzio R. A. Synthesis and subcellular distribution of heparan sulfate in the rat exocrine pancreas. Arch Biochem Biophys. 1977 Jul;182(1):188–196. doi: 10.1016/0003-9861(77)90298-3. [DOI] [PubMed] [Google Scholar]
- Margolis R. K., Jaanus S. D., Margolis R. U. Stimulation by acetylcholine of sulfated mucopolysaccharide release from the perfused cat adrenal gland. Mol Pharmacol. 1973 Jul;9(4):590–594. [PubMed] [Google Scholar]
- Meldolesi J., Marini D., Marini M. L. Studies on in vitro synthesis and secretion of growth hormone and prolactin. I. Hormone pulse labeling with radioactive leucine. Endocrinology. 1972 Sep;91(3):802–808. doi: 10.1210/endo-91-3-802. [DOI] [PubMed] [Google Scholar]
- Nakagami K., Warshawsky H., Leblond C. P. The elaboration of protein and carbohydrate by rat parathyroid cells as revealed by electron microscope radioautography. J Cell Biol. 1971 Dec;51(3):596–610. doi: 10.1083/jcb.51.3.596. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Palade G. Intracellular aspects of the process of protein synthesis. Science. 1975 Aug 1;189(4200):347–358. doi: 10.1126/science.1096303. [DOI] [PubMed] [Google Scholar]
- Pelletier G. Autoradiographic studies of synthesis and intracellular migration of glycoproteins in the rat anterior pituitary gland. J Cell Biol. 1974 Jul;62(1):185–197. doi: 10.1083/jcb.62.1.185. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rambourg A., Racadot J. Identification en microscopie électronique de six types cellulaires dans l'antéhypophyse du Rat à l'aide d'une technique de coloration par le mélange acide chromique-phosphotungstique. C R Acad Sci Hebd Seances Acad Sci D. 1968 Jan 8;266(2):153–155. [PubMed] [Google Scholar]
- Reggio H. A., Palade G. E. Sulfated compounds in the zymogen granules of the guinea pig pancreas. J Cell Biol. 1978 May;77(2):288–314. doi: 10.1083/jcb.77.2.288. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reggio H., Dagorn J. C. Ionic interactions between bovine chymotrypsinogen A and chondroitin sulfate A.B.C.. A possible model for molecular aggregation in zymogen granules. J Cell Biol. 1978 Sep;78(3):951–957. doi: 10.1083/jcb.78.3.951. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Scheele G. A., Palade G. E., Tartakoff A. M. Cell fractionation studies on the guinea pig pancreas. Redistribution of exocrine proteins during tissue homogenization. J Cell Biol. 1978 Jul;78(1):110–130. doi: 10.1083/jcb.78.1.110. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tartakoff A., Greene L. J., Palade G. E. Studies on the guinea pig pancreas. Fractionation and partial characterization of exocrine proteins. J Biol Chem. 1974 Dec 10;249(23):7420–7431. [PubMed] [Google Scholar]
- Uvnäs B. The molecular basis for the storage and release of histamine in rat mast cell granules. Life Sci. 1974 Jun 16;14(12):2355–2366. doi: 10.1016/0024-3205(74)90131-3. [DOI] [PubMed] [Google Scholar]
- Young R. W. The role of the Golgi complex in sulfate metabolism. J Cell Biol. 1973 Apr;57(1):175–189. doi: 10.1083/jcb.57.1.175. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zanini A., Giannattasio G., Nussdorfer G., Margolis R. K., Margolis R. U., Meldolesi J. Molecular organization of prolactin granules. II. Characterization of glycosaminoglycans and glycoproteins of the bovine prolactin matrix. J Cell Biol. 1980 Jul;86(1):260–272. doi: 10.1083/jcb.86.1.260. [DOI] [PMC free article] [PubMed] [Google Scholar]