Temephos decreases ovarian antral follicle growth in an in vitro system

Abstract C-type natriuretic peptide (CNP) encoded by the NPPC (Natriuretic Peptide Precursor C) gene expressed in ovarian granulosa cells inhibits oocyte maturation by activating the natriuretic peptide receptor (NPR)B (NPRB) in cumulus cells. RT-PCR analyses indicated increased NPPC and NPRB expression during ovarian development and follicle growth, associated with increases in ovarian CNP peptides in mice. In cultured somatic cells from infantile ovaries and granulosa cells from prepubertal animals, treatment with CNP stimulated cGMP production. Also, treatment of cultured preantral follicles with CNP stimulated follicle growth whereas treatment of cultured ovarian explants from infantile mice with CNP, similar to FSH, increased ovarian weight gain that was associated with the development of primary and early secondary follicles to the late secondary stage. Of interest, treatment with FSH increased levels of NPPC, but not NPRB, transcripts in ovarian explants. In vivo studies further indicated that daily injections of infantile mice with CNP for 4 d promoted ovarian growth, allowing successful ovulation induction by gonadotropins. In prepubertal mice, CNP treatment alone also promoted early antral follicle growth to the preovulatory stage, leading to efficient ovulation induction by LH/human chorionic gonadotropin. Mature oocytes retrieved after CNP treatment could be fertilized in vitro and developed into blastocysts, allowing the delivery of viable offspring. Thus, CNP secreted by growing follicles is capable of stimulating preantral and antral follicle growth. In place of FSH, CNP treatment could provide an alternative therapy for female infertility.

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In Vitro Assay of Platelet Adhesiveness with Washed and Tanned Human Red Cells

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651281 ◽

1968 ◽

Vol 20 (03/04) ◽

pp. 384-396 ◽

Cited By ~ 1

Author(s):

G Zbinden ◽

S Tomlin

Keyword(s):

Platelet Adhesion ◽

Sodium Citrate ◽

Blood Platelets ◽

In Vitro Assay ◽

Red Cells ◽

Platelet Adhesiveness ◽

Vitro Assay ◽

In Vitro System ◽

Human Red Cells

SummaryAn in vitro system is described in which adhesion of blood platelets to washed and tannic acid-treated red cells was assayed quantitatively by microscopic observation. ADP, epinephrine and TAME produced a reversible increase in platelet adhesiveness which was antagonized by AMP. With Evans blue, polyanetholsulfonate, phthalanilide NSC 38280, thrombin and heparin at concentrations above 1-4 u/ml the increase was irreversible. The ADP-induced increase in adhesiveness was inhibited by sodium citrate, EDTA, AMP, ATP and N-ethylmaleimide. EDTA, AMP and the SH-blocker N-ethylmaleimide also reduced spontaneous platelet adhesion to red cells. No significant effects were observed with adenosine, phenprocoumon, 5-HT, phthalanilide NSC 57155, various estrogens, progestogens and fatty acids, acetylsalicylic acid and similarly acting agents, hydroxylamine, glucose and KCN. The method may be useful for the screening of thrombogenic and antithrombotic properties of drugs.

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The Mesothelial Cell as a Non-Thrombogenic Surface

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661149 ◽

1984 ◽

Vol 52 (02) ◽

pp. 102-104 ◽

Cited By ~ 25

Author(s):

L J Nicholson ◽

J M F Clarke ◽

R M Pittilo ◽

S J Machin ◽

N Woolf

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Blood Flow ◽

Cell Surface ◽

Mesothelial Cell ◽

Mesothelial Cells ◽

Plastic Film ◽

In Vitro System ◽

Scanning Electron

SummaryA technique for harvesting mesothelial cells is described. This entails collagenase digestion of omentum after which the cells can be cultured. The technique has been developed using the rat, but has also been successfully applied to human tissue. Cultured rat mesothelial cells obtained in this way have been examined by scanning electron microscopy. Rat mesothelial cells grown on plastic film have been exposed to blood in an in vitro system using a Baumgartner chamber and have been demonstrated to support blood flow. No adhering platelets were observed on the mesothelial cell surface. Fibroblasts similarily exposed to blood as a control were washed off the plastic.

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