Endocrine Abstracts

Both low-frequency electro-acupuncture (EA) and manual acupuncture improve menstrual frequency and decrease circulating androgens in women with polycystic ovary syndrome (PCOS). We sought to determine whether low-frequency EA is more effective than manual stimulation in regulating disturbed estrous cyclicity in rats with PCOS induced by 5α-dihydrotestosterone (DHT). To identify the central mechanisms of the effects of stimulation, we assessed hypothalamic mRNA expression of molecules that regulate reproductive and neuroendocrine function. From age 70 days, rats received 2-Hz EA or manual stimulation of the needles five times/week for 4–5 weeks; untreated rats served as controls. Specific hypothalamic nuclei were obtained by laser microdissection, and mRNA expression was measured with TaqMan low-density arrays. Untreated rats were acyclic. During the last 2 weeks of treatment, seven of eight (88%) rats in the EA group had epithelial keratinocytes, demonstrating estrous cycle change (P=0.034 vs controls). In the manual group, five of nine (56%) rats had estrous cycle changes (NS vs controls). mRNA expression of the opioid receptors Oprk1 and Oprm1 in the hypothalamic arcuate nucleus was lower in the EA group than in untreated controls. mRNA expression of the steroid hormone receptors Esr2, Pgr, and Kiss1r was lower in the manual group than in the controls. In rats with DHT-induced PCOS, low-frequency EA restored disturbed estrous cyclicity but did not differ from manual stimulation group. Thus EA cannot be considered superior to manual stimulation. The effects of low-frequency EA may be mediated by central opioid receptors, while manual stimulation may involve regulation of steroid hormone/peptide receptors.

Declaration of interest: I fully declare a conflict of interest. Details below.

Funding: This work was supported, however, funding details unavailable.

This study was supported by grants from the Swedish Medical Research Council (project no. 2008-72VP-15445-01A); Novo Nordisk Foundation; Wilhelm and Martina Lundgrensâ€s Science Fund; Hjalmar Svensson Foundation; Adlerbert Research Foundation; Swedish federal government under the LUA/ALF agreement ALFFGBG-10984 and 136481 (E S-V), Chinese Special Fund for Postdoc (no. 200801170) and National Natural Science Foundation of China) (no. 81001544/H2718) (Y F).

Figure 1. Laser microdissection of rat hypothalamic nuclei according to The Rat Brain in Stereotaxic Coordinates (Paxinos and Watson 2009) of rat hypothalamus. (A) Arcuate nucleus (Arc). (B) Medial preoptic area (MPOA). (C) Anteroventral periventricular (Avpv). Scale bar, 500 μm. (D and E). Dissected tissue catapulted into the AdhesiveCaps. Scale bar, 300 μm.