Summary
We report here on the cellular localization in the fish pituitary of somatolactin (SL), a putative new pituitary hormone related to growth hormone and prolactin, which has been recently identified in the piscine pituitary gland. Immunocytochemical staining, using anti-cod SL serum, revealed that in the cod pituitary gland, SL is produced by cells in the intermediate lobe, bordering the neural tissue. These cells, staining weakly with periodic-acid-Schiff (PAS), are distinct from the melanocyte stimulating hormone (MSH) cells which, as in all teleosts, are PAS-negative. SL-immunoreactivity was observed in the same location in all other teleost species examined: flounder, rainbow trout, killifish, molly, catfish and eel. In most fish the SL-immunoreactive cells are either strongly or weakly PAS-positive but in rainbow trout are chromophobic, indicating that the SL protein can probably exist in glycosylated and non-glycosylated forms. Thus, in demonstrating the cellular localization of SL, this study provides the first identification of the enigmatic, second cell-type of the fish pars intermedia.
Similar content being viewed by others
References
Baker BI (1963) Effect of adaptation to black and white backgrounds on the teleost pituitary. Nature 198:404
Baker BI, Ball JN (1970) Background adaptation and the pituitary in teleost fishes. J Endocrinology 48:26–27
Ball JN, Baker BI (1969) The pituitary gland: anatomy and histophysiology. In: Hoar WS, Randall RJ (eds) Fish Physiology. Academic Press, New York, pp 1–110
Ball JN, Batten TFC (1981) Pituitary and melanophore responses to background in Poecillia latipinna (Teleostei): role of the pars intermedia PAS cells. Gen Comp Endocrinol 44:233–248
Ball JN, Uchiyama M, Pang PKT (1982) Pituitary responses to calcium deprivation in a euryhaline teleost, Fundulus heteroclitus, adapted to artificial seawater. Gen Comp Endocrinol 46:480–485
Benjannet S, Leduc R, Lazure C, Seidah NG, Marcinkiewicz M, Chretien M (1985) GAWK, a novel human pituitary polypeptide: isolation, immunocytochemical localization and complete amino acid sequence. Biochem Biophys Res Commun 126:602–609
DePalatis LR, Fiorindo RP, Ho RH (1982) Substance P immunoreactivity in the anterior pituitary gland of the guinea pig. Endocrinology 110:282–284
Duckworth ML, Peden LM, Schroedter I, Shah P, Friesen HG (1981) Placental lactogens and the extrahypophyseal prolactin gene family. In: Hoshino K (ed) Prolactin gene family and its receptors. Elsevier, Amsterdam, pp 79–88
Eys van GJJM (1980) Structural changes in the pars intermedia of the cichlid teleost Sarotherodon mossambicus as a result of background adaptation and illumination. II. The PAS-positive cells. Cell Tissue Res 210:171–179
Goldstein A, Ghazarossian VE (1980) Immunoreactive dynorphin in pituitary and brain. Proc Natl Acad Sci USA 77:6207–6210
Kawauchi H (1983) Chemistry of proopiomelanocortin-related peptides in the salmon pituitary. Arch Biochem Biophys 227:343–350
Laemmli UK (1970) Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227:680–685
Moons L, Cambre M, Ollevier F, Vandesande F (1989) Immunocytochemical demonstration of close relationships between neuropeptidergic nerve fibers and hormone-producing cell types in the adenohyphophysis of the sea bass (Dicentrarchus labrax). Gen Comp Endocrinol 73:270–283
Naito N, Takahashi A, Nakai Y, Kawauchi H (1984) Immunocytochemical identification of the proopiomelanocortin-producing cells in the chum salmon pituitary with antisera to endorphin and NH2-terminal peptide of salmon proopiocortin. Gen Comp Endocrinol 56:185–192
Olivereau M, Olivereau JM (1981) Calcium-sensitive cells of the pars intermedia and osmotic balance in the eel. I. Responses to changes in the environmental calcium and magnesium. Cell Tissue Res 222:231–241
Olivereau M, Olivereau JM, Aimar C (1981) Specific effect of calcium ions on the calcium-sensitive cells of the pars intermedia in the goldfish. Cell Tissue Res 214:23–31
Olivereau M, Olivereau JM, Aimar C (1985) Control of MSH-and PAS-positive cells in the pars intermedia of the goldfish. In: Lofts B, Holmes WN (eds) Current trends in comparative endocrinology. Hong Kong University Press, Hong Kong, pp 145–147
Olivereau M, Olivereau JM, Lambert JF (1987) Differential effect of sodium and magnesium on the pituitary of goldfish adapted to calcium-free environments. Acta Zool 68:71–78
Olivereau M, Olivereau J, Vandesande F (1990) Localization of growth hormone-releasing factor-like immunoreactivity in the hypothalamo-hypophyseal system of some teleost species. Cell Tissue Res 259:73–80
Ono M, Takayama Y, Rand-Weaver M, Sakata S, Yasunaga T, Noso T, Kawauchi H (1990) cDNA cloning of somatolactin, a new pituitary protein related to growth hormone and prolactin. Proc Natl Acad Sci USA 87:4330–4334
Pang PKT, Griffith RW, Schreibman MP (1973) The pituitary gland and calcium metabolism in Fundulus diaphanus (Teleostei). Gen Comp Endocrinol 20:358–361
Parsons JA, Gray D, Rafferty B, Zanelli JM (1978) Evidence for a hypercalcaemic factor in the fish pituitary immunologically related to mammalian parathyroid hormone. In: Copp DH, Talmage RV (eds) Endocrinology of calcium metabolism. Excerpta Medica, Amsterdam, pp 111–114
Rand-Weaver M, Walther BT, Kawauchi H (1989) Isolation and characterization of growth hormone from Atlantic cod (Gadus morhua). Gen Comp Endocrinol 73:260–269
Rand-Weaver M, Noso T, Muramoto K, Kawauchi H (1991) Isolation and characterization of somatolactin, a new protein related to growth hormone and prolactin from Atlantic cod (Gadus morhua) pituitary glands. Biochemistry (in press)
Rawdon BB (1979) Immunostaining of n-cells in the rostral pars distalis and PAS-positive cells in the pars intermedia of a teleost (Sarotherodon massambicus) by antisera to mammalian prolactins. Gen Comp Endocrinol 37:374–382
Schreibman MP, Margolis-Kazan H, Halpens LP (1980) LH-RH and gonadotropin in neonatal platyfish (Xiphophorus maculatus). Am Zool 20:729
Seidah NG, Hsi KL, De Serres G, Rochemont J, Hamelin J, Antakly T, Cantin M, Chretien M (1983) Isolation and NH2-terminal sequence of a highly conserved human and porcine pituitary protein belonging to a new superfamily: immunochemical localization in the pars distalis and pars nevrosa of the pituitary and in the supraoptic nucleus of the hypothalamus. Arch Biochem Biophys 225:525–534
Steele MK, Brownfield MS, Ganong WF (1982) Immunocytochemical localization of angiotensin immunoreactivity in gonadotrophs and lactotrophs of the rat anterior pituitary gland. Neuroendocrinol 35:155–158
Takayama Y, Ono M, Rand-Weaver M, Kawauchi H (1991) Greater conservation of somatolactin, a presumed pituitary hormone of the growth hormone/prolactin family, than growth hormone in teleost fish. Gen Comp Endocrinol (in press)
Wendelaar-Bonga SE, Meij van der JC, Flik G (1986) Response of PAS-positive cells of the pituitary pars intermedia cells in the teleost Carassius auratus to acid water. Cell Tissue Res 243:609–617
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Rand-Weaver, M., Baker, B.J. & Kawauchi, H. Cellular localization of somatolactin in the pars intermedia of some teleost fishes. Cell Tissue Res 263, 207–215 (1991). https://doi.org/10.1007/BF00318762
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00318762