Changes in distribution of phosphomannosyl receptors during maturation of rat spermatozoa

BELMONTE, SILVIA A; ROMANO, PATRICIA; FORNES, WALTER M; SOSA, MIGUEL ANGEL

BIOLOGY OF REPRODUCTION (ONLINE)

Academic Press, Inc

Lugar: New York, USA; Año: 2000 vol. 63 p. 1172 - 1178

1529-7268

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Changes in distribution of phosphomannosyl receptors during maturation of rat spermatozoa. Belmonte SA, Romano PS, Fornés WM, Sosa MA.   Instituto de Histología y Embriología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina. sbelmont@fmed2.uncu.edu.ar   The aim of the present work was to study the distribution of the cation-independent (CI) and cation-dependent (CD) mannose-6-phosphate receptors (MPRs) in spermatozoa obtained from either rete testis or three regions of rat epididymis. We observed that both receptors underwent changes in distribution as spermatozoa passed from rete testis to cauda epididymis. CI-MPR was concentrated in the dorsal region of the head in rete testis sperm and that this labeling extended to the equatorial segment of epididymal spermatozoa. CD-MPR, however, changed from a dorsal distribution in rete testis, caput, and corpus to a double labeling on the dorsal and ventral regions in cauda spermatozoa. The percentages of spermatozoa that showed staining for either CI-MPR or CD-MPR increased from rete testis to epididymis. The observed changes were probably the result of a redistribution during transit rather than an unmasking of receptors. The fluorescence corresponding to CD-MPR and CI-MPR on the dorsal region disappeared when caudal spermatozoa underwent the acrosomal reaction. Receptors were localized on the plasmalemma of spermatozoa, as observed by immunoelectron microscopy. Changes in distribution may be related to a maturation process, which suggests new roles for the phosphomannosyl receptors.   PMID: 10993842 [PubMed - indexed for MEDLINE Biol Reprod. 2000 Oct;63(4):1172-8.