Changes in ectonucleotidase activities in rat Sertoli cells during sexual maturation.
Sertoli cell maturation is a complex process involving both morphological and biochemical changes. These cells have previously been shown to be targets for extracellular purine structures such as ATP and adenosine. These compounds evoke responses in rat Sertoli cells through the purinoceptor families, P2X and P2Y and PA1. The signals to purinoceptors are usually terminated by the action of ectonucleotidases. In a previous work, we demonstrated that rat Sertoli cells have ecto-ATPdiphosphohydrolase (EC 3.6.1.5), ecto-5'-nucleotidase (EC 3.1.3.5) and ecto-adenosine deaminase (ecto-ADA) (EC 3.5.4.4) activities. Here we investigated whether some changes occur during rat Sertoli cell maturation in these activities. Rat Sertoli cells obtained from rats of different ages representing the pre-pubertal, mid-pubertal and 'young adult' (10-, 18- and 35-day-old, respectively) were cultured and used for different assays. The nucleotide hydrolysis was estimated by measuring the Pi released using a colorimetric method and by HPLC analysis. ATP and ADP hydrolysis was increased 3-fold during sexual maturation. AMP hydrolysis increased 4-fold in 10- to 35-day-old Sertoli cells. Similar results were obtained when we used other substrates to measure the extracellular hydrolysis of nucleotides (GTP, GDP, GMP and IMP). The ecto-ADA activity showed a 2-fold increase in the specific activity (18- to 35-day-old Sertoli cells). The termination of the purine cascade by adenosine degradation was faster in the 35- than in 18-day-old Sertoli cells. Follicle Stimulating Hormone (FSH) influences on the ectonucleotidase activities were investigated in 10- and 18-day-old Sertoli cells and a significant increase in the ATP and ADP hydrolysis was observed. Our results show an increase in the extracellular purine cascade during the Sertoli cell development, indicating a rise in the purine communication inside the seminiferous tubules with rat sexual maturation.
Casali
Emerson André
EA
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
de Souza
Luiz Fernando
LF
Gelain
Daniel Pens
DP
Kaiser
Glória Regina Rodrigues de Freitas
GR
Battastini
Ana Maria Oliveira
AM
Sarkis
João José Freitas
JJ
D015720:5'-Nucleotidase / Q000378:metabolism*; D000243:Adenosine Deaminase / Q000378:metabolism*; D000244:Adenosine Diphosphate / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006868:Hydrolysis; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012708:Sertoli Cells / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D012741:Sexual Maturation / Q000502:physiology*
D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D005640:Follicle Stimulating Hormone; D015720:5'-Nucleotidase; D000243:Adenosine Deaminase; D000251:Adenosine Triphosphatases; C027201:ectoATPase