PMID- 9770782 OWN - NLM STAT- MEDLINE DCOM- 19981202 LR - 20191210 IS - 0967-1994 (Print) IS - 0967-1994 (Linking) VI - 6 IP - 2 DP - 1998 May TI - Localisation of inositol trisphosphate and ryanodine receptors during mouse spermatogenesis: possible functional implications. PG - 159-72 AB - During spermatogenesis the activity of intracellular Ca(2+)-release channels is likely to play an important role in different specific cellular functions. Accordingly, messenger RNAs for the three inositol 1,4,5-trisphosphate receptor (IP3R) subtypes were found to be present throughout spermatogenesis. Immunocytochemical analysis revealed distinct distribution patterns of the mature IP3Rs during sperm differentiation. At early stages, IP3Rs are distributed throughout the cytoplasm, and as differentiation proceeds they become selectively localised to the Golgi complex. Consistently, spermatogonia underwent large intracellular Ca2+ release in response to thapsigargin (TG), while smaller responses were detected in late spermatocytes and spermatids. The distribution of IP3Rs and the larger Ca(2+)-release responses found in spermatogonia, suggest that IP3Rs may be involved in cell proliferation at this stage. This notion is supported by our observations in a spermatogenic cell line that depletion of intracellular Ca2+ pools using TG inhibits cell division, and that incubation with an IP3R-I antisense oligonucleotide completely inhibited proliferation. Furthermore, the three genes encoding ryanodine receptor proteins (RyRs) are expressed at all stages of spermatogenesis. However, immunocytochemical studies with specific antibodies against each of the RyR subtypes detected types 1 and 3 in spermatogenic cells and only type 3 in mature sperm. In contrast to IP3Rs, RyRs remain scattered in the cytoplasm throughout differentiation. Functional responses to caffeine and ryanodine were absent in spermatogenic cells and in mature sperm. These findings suggest that IP3Rs have significantly more important roles in spermatogenesis than RyRs, and that one of these roles is crucial for cell proliferation. FAU - Trevino, C L AU - Trevino CL AD - Instituto de Biotecnologia-UNAM, Cuernavaca, Morelos, Mexico. FAU - Santi, C M AU - Santi CM FAU - Beltran, C AU - Beltran C FAU - Hernandez-Cruz, A AU - Hernandez-Cruz A FAU - Darszon, A AU - Darszon A FAU - Lomeli, H AU - Lomeli H LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - England TA - Zygote JT - Zygote (Cambridge, England) JID - 9309124 RN - 0 (Calcium Channels) RN - 0 (Indoles) RN - 0 (Inositol 1,4,5-Trisphosphate Receptors) RN - 0 (Oligonucleotides, Antisense) RN - 0 (RNA, Messenger) RN - 0 (Receptors, Cytoplasmic and Nuclear) RN - 0 (Ryanodine Receptor Calcium Release Channel) RN - 67526-95-8 (Thapsigargin) RN - EC 7.2.2.10 (Calcium-Transporting ATPases) RN - X9TLY4580Z (cyclopiazonic acid) SB - IM MH - Animals MH - Calcium Channels/genetics/*isolation & purification MH - *Calcium Signaling MH - Calcium-Transporting ATPases/antagonists & inhibitors MH - Cell Compartmentation MH - Cell Differentiation MH - Cell Division/drug effects MH - Epididymis/cytology MH - Immunohistochemistry MH - Indoles/pharmacology MH - Inositol 1,4,5-Trisphosphate Receptors MH - Male MH - Mice MH - Oligonucleotides, Antisense/pharmacology MH - Polymerase Chain Reaction MH - RNA, Messenger/isolation & purification MH - Receptors, Cytoplasmic and Nuclear/genetics/*isolation & purification MH - Ryanodine Receptor Calcium Release Channel/genetics/*isolation & purification MH - Spermatids/physiology MH - *Spermatogenesis MH - Spermatogonia/physiology MH - Thapsigargin/pharmacology EDAT- 1998/10/15 00:00 MHDA- 1998/10/15 00:01 CRDT- 1998/10/15 00:00 PHST- 1998/10/15 00:00 [pubmed] PHST- 1998/10/15 00:01 [medline] PHST- 1998/10/15 00:00 [entrez] AID - 10.1017/s0967199498000094 [doi] PST - ppublish SO - Zygote. 1998 May;6(2):159-72. doi: 10.1017/s0967199498000094.