The expression and function of gonadotropin receptors, and the secretion of steroids, transferrin, and cytokines were investigated in three immortalized (single transfection with v-myc) mouse granulosa cell lines (GRM01, GRM01L, and GRM02). A dose-dependent increase in progesterone production was obtained in GRM01 and GRM02 cells after addition of LH, FSH, modulators of the adenylate cyclase enzyme system, and cAMP analogues. The LH-induced release of progesterone was already detectable in GRM02 cells after 8 h and was related to incubation time and cell number. Both epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha) induced the secretion of progesterone in GRM02 cells, while no effect was obtained with TGF beta. LH receptor concentration was highest in the GRM02 cell line. FSH receptor mRNA was visualized in GRM01 and GRM02 cells. Aromatase activity in GRM02 cells was induced by androgens and inhibited by aromatase inhibitors. Whereas all cell lines were able to secrete transferrin, only in GRM01 cells was transferrin secretion increased significantly by LH. FSH did not affect transferrin secretion in the three cell lines, in contrast to forskolin or 8-bromo-cAMP. The immortalized mouse granulosa cell lines were able to express and release several growth factors. The expression and secretion of activin, inhibin, TGF beta, EGF, TGF alpha, insulin-like growth factor II, fibroblast growth factor (acidic and basic), platelet-derived growth factor, and interleukin-6 suggest an autocrine or paracrine role for these factors in follicular differentiation and function. In conclusion, these cells, derived from mural granulosa cells and immortalized in a preovulatory state, can be used to study granulosa cell physiology or to study the role of granulosa cells and their derivatives in the process of follicular maturation, fertilization, and early embryonic development.

The concentration and the heterogeneity of alpha-1-acid glycoprotein (alpha-1-AGP) and oxprenolol binding were determined in serum of healthy dogs and dogs with inflammatory disease. In inflammation, an increase in the mean alpha-1-AGP concentration from 0.47 to 2.85 g/l was accompanied by a reduction in the mean free oxprenolol fraction from 25% to 6%. alpha-1-AGP concentration and oxprenolol binding were inversely correlated. The heterogeneity of canine alpha-1-AGP remained essentially unchanged in dogs with inflammation and, in both these dogs and the controls, between five and seven forms with different isoelectric points and one single concanavalin A-reactive form were detected. It is concluded that in dogs, as in humans, oxprenolol binds to serum alpha-1-AGP. Changes in serum binding of oxprenolol during inflammation result from a change in the serum concentration of alpha-1-AGP rather than a change of molecular heterogeneity.

Inter-individual variation in drug serum protein binding was studied in healthy dogs and in dogs with inflammatory diseases for lidocaine, oxprenolol and propranolol, which bind mainly to alpha 1-acid glycoprotein (alpha 1-AGP), and for diazepam, digitoxin and phenytoin, which bind mainly to albumin. For the drugs mostly bound to alpha 1-AGP, in both groups of dogs binding varied considerably, and it was markedly higher in dogs with inflammatory disease. For the other drugs, the variation in binding was smaller and did not differ between the two groups of dogs. In both groups of dogs, the alpha 1-AGP concentration varied widely; it was higher in the serum of the dogs with inflammation, while the concentration of albumin was lower in these animals. There was a significant negative correlation between percentage free lidocaine, oxprenolol or propranolol and alpha 1-AGP concentration, suggesting that the inter-individual variation in binding of these drugs is due to the variation in alpha 1-AGP concentration. There was a marked intra-individual variation in lidocaine binding and in serum alpha 1-AGP concentration, studied over a period of 3 weeks in healthy dogs; a significant negative correlation between percentage free lidocaine and alpha 1-AGP concentration was obtained.

No abstract

1. alpha 1‐acid glycoprotein (AAG) concentration and molecular heterogeneity, and oxprenolol protein binding were studied in serum of 15 healthy volunteers, 14 patients with lung carcinoma and 17 patients with liver cirrhosis. 2. The AAG serum concentration was increased to 180.7% in patients with lung cancer and decreased to 73.4% in cirrhotic patients as compared with controls (P less than 0.05). 3. The concanavalin A (conA) dependent heterogeneity of serum AAG was very similar in controls and patients with lung cancer: a ratio of 9/9/2 was obtained for the conA nonreactive, the conA weakly reactive and the conA strongly reactive subfraction respectively; in cirrhotic patients, the ratio shifted to 11/7/1. 4. The heterogeneity in electric charge, demonstrated by isoelectric focusing, was similar in the three groups of subjects: 70‐80% of the focussed bands were found in the main three bands. 5. The binding of oxprenolol to serum proteins was increased in lung tumour patients and decreased in liver cirrhotic patients as compared with controls (P less than 0.05). There was no change in binding affinity and oxprenolol binding was significantly correlated to total AAG serum concentration and to the concentration of each of the conA dependent subtypes, in controls as well as in both patients groups.