Yes, that study is stupid since you can't compare two drugs like that.
They noticed a significant difference between Clomid and Nolvadex in their effect on LH response to GHRH...
That may or may not be important since we know that LH/test increase induced by Clomid can be sustained for a long time.
Similar effect of Clomid on pituitary response to LHRH was noticed in some other studies also:
Pituitary responsiveness to LHRH and TRH in men: effect of bromocriptine and clomiphene treatment.
Ronnberg L, Ylikorkala O.
The effect of the concomitant use of bromocriptine and clomiphene on pituitary function was tested in 8 healthy men, who ingested either 100 mg of clomiphene, 5 mg of bromocriptine or 100 mg of clomiphene +5 mg of bromocriptine daily for 7 days. Plasma concentrations of FSH and LH increased similarly during clomiphene and clomiphene + bromocriptine intake. Bromocriptine decreased the plasma levels of prolactin (Prl) and this decrease was unaffected by clomiphene.The latter blunted the plasma LH response to LHRH whilst bromocriptine blunted the Prl response to TRH, but Clomiphene and bromocriptine together had no additive effects on gonadotrophin and Prl secretion. It thus seems likely that this combination offers no advantage over clomiphene alone in the treatment of normoprolactinaemic infertile men
Pituitary response to exogenous LHRH in superovulated women.
Messinis IE, Templeton AA.
Department of Obstetrics and Gynaecology, University of Aberdeen, Foresterhill, UK.
The response of the pituitary to exogenous LHRH was investigated in 9 normally ovulating women during the late follicular phase of a spontaneous (control) cycle, a cycle during treatment with clomiphene and a cycle during treatment with 'pure' FSH. During clomiphene treatment, basal FSH concentrations increased significantly up to Day 6 of the cycle and then decreased progressively while basal LH values showed a continuous rise. During treatment with FSH, basal LH concentrations decreased significantly. The response of both FSH and LH to LHRH showed a significant and quantitatively similar decrease during clomiphene or FSH administration as compared to the spontaneous cycles. It is suggested that basal secretion of FSH and LH is regulated by two separate mechanisms, and that an ovarian inhibitory factor(s) attenuates the response of both FSH and LH to exogenous LHRH and possibly the endogenous LH surge in superovulated cycles.
Clin Endocrinol (Oxf) 1976 Mar;5(2):175-80 Related Articles, Links
Modulation of pituitary responsiveness to exogenous LHRH by an oestrogenic and an anti-oestrogenic compound in the normal male.
Dhont M, de Gezelle H, Vandekerckhove D.
The effect of clomiphene (100 mg daily for 10 days) and ethinyl oestradiol (100 mug daily for 10 days) on the gonadotrophin response to synthetic LHRH has been investigated in two groups of five normal males. A third group of five men served as control group. LHRH, 25 mug, was injected intravenously on days 0, 4, 7 and 10 and the response of serum LH and FSH was monitored by radioimmunoassay. In contrast to the wide inter-individual variation of the response pattern, the intra-individual variation of the response to LHRH in the control group was small.Clomiphene induced a significant elevation of the baseline levels of LH and FSH after a few days of treatment; the pituitary responsiveness to LHRH, however, was significantly reduced. Oestrogen treatment resulted in a uniform suppression of both basal gonadotrophin levels and pituitary responsiveness. The decreased gonadotrophin response to LHRH during clomiphene treatment is thought to be caused by a relative and temporary pituitary depletion of the releasable gonadotrophin content. Although the suppression of LH and FSH response during oestrogen treatment may point to a direct inhibitory effect of oestrogen on pituitary gonadotrophin release, an indirect hypothalamic pathway, through suppression of endogenous LHRH, cannot be ruled out.
J Clin Endocrinol Metab 1976 Mar;42(3):593-4 Related Articles, Links
Effect of clomiphene on basal and LRH-induced gonadotropin secretion in postmenopausal women.
Hashimoto T, Miyai K, Izumi K, Kumahara Y.
LRH tests were performed in 11 postmenopausal women before and after the administration of 200 mg of clomiphene citrate daily by mouth for 7 consecutive days. The basal levels and the maximum increments of serum LH (deltaLH) and the area under the response curve from basal level (deltaarea) after LRH administration, significantly (P less than 0.005) decreased after consecutive administration of this compound. Serum FSH levels were significantly (P less than 0.025) decreased but deltaFSH and deltaarea in LRH test were statistically unchanged. These results suggest that clomiphene citrate in postmenopausal women inhibits the pituitary gonadotropin response to exogenous LRH by its estrogenic effects.