Summary
The ultrastructural immunohistochemical localization of gamma aminobutyric acid (GABA) and its regulating enzymes, l-glutamate decarboxylase (GAD) and gamma aminobutyrate-α-ketoglutarate transaminase, was determined utilizing an immunogold post-embedding protocol in pancreatic exocrine tissue. Within the acinar cell, GABA and its biosynthetic enzyme, GAD, were localized in zymogen granules. Quantitative analysis of the GABA immunoreactivity in the acinar cell revealed 1.7±0.5 gold particles/μm2 over the cytoplasm, 36.6±14.1 gold particles/ μm2 over the zymogen granules, and 2.9±2.1 gold particles /μm2 over the mitochondria. Quantitative analysis of the distribution of colloidal gold particles, representing glutamate decarboxylase immunoreactivity in the acinar cells, revealed 38.4±2.5 gold particles/μm2 over the zymogen granules, 4.7±1.1 gold particles/μm2 over the mitochondria and 6.3±0.5 gold particles/μm2 over the remainder of the cytoplasm. Substitution of normal sheep serum for the sheep anti-glutamate decarboxylase serum revealed a significant (p< 0.001) decrease of the colloidal gold particle distribution over the zymogen granules and cytoplasmic compartments of the acini. Gamma aminobutyrate -α-ketoglutarate transaminase, the catabolic enzyme for GABA, was not detected in the mitochondria, zymogen granules, and cytoplasm of the acinar cell, suggesting that GABA is not catabolized within the acinar cell. Preabsorption and substitution controls resulted in an absence of labeling. These results suggest that GABA may act extracellularly and/or have a role within the zymogen granule in the exocrine pancreas.
Similar content being viewed by others
References
Barker JL, Ransom BR (1978) Amino acid pharmacology of mammalian central neurons grown in tissue culture. J Physiol (Lond) 280:331–354
Case RM, Argent BE (1986) Bicarbonate secretion by pancreatic duct cells: Mechanisms and control. In: Go VLW, Brooks FP, DiMagno EP, Gardner JD, Lebenthal E, Scheele GA (eds) The exocrine pancreas: Biology, pathobiology, and diseases. Raven Press, New York, pp 213–244
Chan-Palay V, Wu J-Y, Palay SL (1979) Immunocytochemical localization of gamma aminobutyric acid transaminase at cellular and ultrastructural levels. Proc Natl Acad Sci USA 76: 2067–2071
Clemente F, Meldolesi J (1975) Calcium and pancreatic secretion. I. Subcellular distribution of calcium and magnesium in the exocrine pancreas of the guinea pig. J Cell Biol 65:88–102
DeLisle RC, Hopfer U (1986) Electrolyte permeabilities of pancreatic zymogen granules: implications for pancreatic secretion. J Cell Biol 250:G489-G496
Garry DJ, Sorenson RL, Coulter HD (1987a) Ultrastructural localization of gamma amino butyric acid (GABA) immunoreactivity in B cells of the rat pancreas. Diabetalogia 30:115–119
Garry DJ, Coulter HD, McIntee TJ, Wu J-Y, Sorenson RL (1987b) Immunoreactive GABA transaminase, within the pancreatic islet, is localized in mitochondria of the B cell. J Histochem Cytochem 35:831–836
Gerber JC, Hare TA (1980) GABA in peripheral tissues: Presence and actions in endocrine pancreatic function. Brain Res Bull 5:341–346
Gershon MD, Ross LL (1966) Location of sites of 5-hydroxytryptamine storage and metabolism by radioautography. J Physiol 186:477–492
Gold MR, Martin AR (1984) Gamma aminobutyric acid and glycine activate Cl- channels having different characteristics in CNS neurones. Nature 308:639–641
Hendrickson AE, Ogren MP, Vaughn JE Barber RP, Wu J-Y (1983) Light and electron microscopic immunocytochemical localization of glutamic acid decarboxylase in monkey geniculate complex: Evidence for GABAergic neurons and synapses. J Neurosci 3:1245–1262
Kitayama S, Tsujimoto A (1986) Involvement of GABAergic mechanisms in the catecholamine secretion from adrenal medulla. In: Erdo SL, Bowery NG (eds) GABAergic Mechanisms in the Mammalian Periphery. Raven Press, pp 249–259
Kuriyama K, Roberts E, Kakefuda T (1968) Association of the gamma aminobutyric acid system with a synaptic vesicle fraction from mouse brain. Brain Res 8:132–152
Maley BE, Newton BW (1985) Immunohistochemistry of gamma aminobutyric acid in the cat nucleus tractus solitarius. Brain Res 330:364–368
Novikoff AB, Essner E, Goldfischer S, Haus M (1962) Nucleosidephosphatase activities of cytomembranes. In: Harris RC (eds) The Interpretation of Ultrastructure. Academic Press, New York, pp 149–192
Oertle WH, Schmechel DE, Mugnaini E, Tappaz ML, Kopin IJ (1981a) Immunocytochemical localization of glutamate decarboxylase in rat cerebellum with a new antiserum. Neuroscience 6:2715–2735
Oertel WH, Schmechel DE, Tappaz ML, Kopin IJ (1981b) Production of a specific antiserum to rat brain glutamic acid decarboxylase by injection of an antigen-antibody complex. Neuroscience 6:2689–2700
Okada Y, Taniguchi H, Baba S (1976) High concentration of GABA and high glutamate decarboxylase activity in rat pancreatic islets and human insulinoma. Science 194:620–622
Reggio HA, Palade GE (1978) Sulfated compounds in the zymogen granules of the guinea pig pancreas. J Cell Biol 77:288–314
Reusens-Billen B, Pirlot X, Remacle C, Hoet JJ, de Gasparo M (1984) Localization of GABA high-affinity binding sites in the pancreas of neonatal rat. Cell Tissue Res 235:503–508
Roberts E (1986) What do GABA neurons really do? They make possible variability generation in relation to demand. Exp Neurol 93:279–290
Roberts E, Kuriyama K (1968) Biochemical-physiological correlations in studies of the gamma amino butyric acid system. Brain Res 8:1–35
Roth J, Berger EG (1982) Immunocytochemical localization of galactosyltransferase in HeLa cells: Codistribution with thiamine pyrophosphatase in trans golgi cisternae. J Cell Biol 93:223–229
Scheele G (1986) Regulation of gene expression in the exocrine pancreas. In: Go VLW, Brooks FP, DiMagno EP, Gardner JD, Lebenthal E, Scheele GA (eds) The exocrine pancreas: Biology, pathobiology, and diseases. Raven Press, New York, pp 55–67
Somogyi P, Hodgson AJ, Chubb IW, Penke B, Erdei A (1985) Antisera to gamma aminobutyric acid. II. Immunocytochemical application to the central nervous system. J Histochem Cytochem 33:240–248
Tsuji M, Nakajima T (1978) Studies on the formation of gamma aminobutyric acid from putrescine in rat organs and purification of its synthetic enzyme from rat intestine. J Biochem 83:1407–1412
Van den Pol AN (1985) Dual ultrastructural localization of two neurotransmitter-related antigens: Colloidal gold-labeled neurophysin-immunoreactive supraoptic neurons receive peroxidase-labeled glutamate decarboxylaseor gold-labeled GABA-immunoreactive synapses. J Neurosci 5:2940–2954
Williams JA, Hootmann SR (1986) Stimulus-secretion coupling in pancreatic acinar cells. In: Go VLW, Brooks FP, DiMagno EP, Gardner JD, Lebenthal E, Scheele GA (eds) The exocrine pancreas: biology pathobiology, and diseases. Raven Press, New York, pp 123–139
Wong E, Schousboe A, Saito D, Wu J-Y, Roberts E (1974) Immunochemical studies of brain glutamate decarboxylase and GABA-transaminase of six inbred strains of mice. Brain Res 68:133–142
Wu J-Y, Lin C-T, Lin H, Xu Y Liu J-W, Hwang BH, Wei SC (1986) Immunochemical characterization and immunohistochemical localization of glutamate decarboxylase and GABA transaminase in peripheral tissues. In: Erdo SL, Bowery NG (eds) GABAergic mechanisms in the mammalian periphery. Raven Press, New York, pp 19–34
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Garry, D.J., Garry, M.G. & Sorenson, R.L. Ultrastructural immunocytochemical localization of l-glutamate decarboxylase and GABA in rat pancreatic zymogen granules. Cell Tissue Res. 252, 191–197 (1988). https://doi.org/10.1007/BF00213841
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00213841