title: Changes in parathyroid hormone-related peptide receptor binding in the shell gland of laying hens (Gallus domesticus) during the oviposition cycle.
abstract: In this study, parathyroid hormone (PTH) receptor binding was examined in the membrane fraction of the endometrium of the shell gland of laying and nonlaying hens by the use of (125)I-PTH-related peptide (PTHrP) binding assays. Specific (125)I-PTHrP binding was found in the endometrium of the shell gland and increased during the first 1 h of incubation and then reached a plateau. Specific (125)I-PTHrP binding increased in line with an increase in protein concentration from 10 to 80 microg. The membrane fraction had specific binding to (125)I-PTHrP. The Scatchard plot analysis revealed a linear profile that indicated the presence of one type of receptor. The equilibrium dissociation constant (K(d)) and the maximum binding capacity (B(max)) in the shell gland decreased 19 h before oviposition in egg-laying hens and remained low for about 20 h during the period of calcification. In contrast, the K(d) and the B(max) in nonlaying hens were constant throughout a 24-h period. These results suggest that PTH acts on the endometrium of the shell gland during the eggshell calcification.
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ieda
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: N
authors.initials: N
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Yasuoka
authors.forename: M
authors.initials: M
authors.lastname: Kawashima
authors.forename: K
authors.initials: K
authors.lastname: Shimada
mesh_terms: D000818:Animals; D002113:Calcification, Physiologic / Q000502:physiology; D002645:Chickens / Q000378:metabolism*; D004528:Egg Shell / Q000378:metabolism*; D005088:Exocrine Glands / Q000378:metabolism*; D005260:Female; D007457:Iodine Radioisotopes; D007700:Kinetics; D008565:Membrane Proteins / Q000096:biosynthesis; D008566:Membranes / Q000378:metabolism; D010058:Oviposition / Q000502:physiology*; D044168:Receptor, Parathyroid Hormone, Type 1; D018016:Receptors, Parathyroid Hormone / Q000378:metabolism*
chemical_list: D007457:Iodine Radioisotopes; D008565:Membrane Proteins; D044168:Receptor, Parathyroid Hormone, Type 1; D018016:Receptors, Parathyroid Hormone