Effects Of Adiponectin On Reproductive Endocrine Of Pituitary Of Wannanhua Pigs

Wannanhua pig is the local breed in Huangshan, China, which has thecharacteristics of early maturity and high reproduction rate. Adp, as one of theadipokines secreted by adipose tissues with a variety of biological effects, had closelyrelationship with the reproduction particularly. The developmental patterns andgender differences of LH and FSH in blood, AdpR1, AdpR2mRNA andreproduction-related factors mRNA expressions in pituitary of Wanna nhua pigs, andtheir correlation were analyzed in order to observe the inner relationship of Adp andreproduction in Wannanhua pigs. In addition, the effects of rAdp on cultured pituitarygland cells of Wannanhua pigs were also studied in this paper in order to recognicethe influence of Adp on gonadotropine synthesis and secretion in Wannanhua pigs,and its possible mechanism.1Developmental patterns and Gender differences of serum gonadotropine, andAdpR1, AdpR2, reproduction-related factors mRNA expressions in pituitary ofWannanhua pigs.Wannanhua pigs were supplied by the Wannanhua pigs reproductive center of Anhuiprovince inYi County. Five Wannan Hua boars and five sows at birth,30,45,90and180days of age were selected. The expression of AdpR1, AdpR2, GnRHR, LH-β andFSH-β mRNA in pituitary were detected by Real-time fluorescent quantitative PCR(qRT-PCR). The concentration of serum LH and FSH at different days of age weredetected by ELISA.(1) The concentration of LH and FSH were significantly changed with ageincreasing (P<0.01), and development patterns of them were seemed similar, Thereare peaks at30d and90d. Serum LH had no gender differences. but FSH contents ingilts were higher than those of boars at30d,45d and180d（P<0.05）.(2) The significant development patterns of AdpR1and AdpR2were seemedsimilar with decreasing at first, then increasing, and decreasing at last. The expressionof AdpR2mRNA were significantly changed with age increasing（P<0.05）which getsthe peaks at0d and45d; The mRNA expression of AdpR1were significantly higherthan AdpR2at any days of age（P<0.05）, while the expression of AdpR1at0d、30dand180d of boars were significantly higher than those of gilts.(3) The development patterns of GnRHR、LH-β and FSH-β mRNA were seemedsimilar, which get the peaks at30d and90d; The expression of LH-β mRNA were significantly changed with age increasing (P<0.05). LH-β and GnRHR mRNAexpression at90d were significantly higher than those at0d（P <0.05or P<0.01）.(4) The analysis of correlation:In pituitary, significant positive correlation was found between mRNAexpressions of AdpR1and AdpR2(r=0.752, P<0.01). The expression of AdpR2werenegatively correlated with GnRHR (r=-0.413, P<0.05). GnRHR were significantlypositive correlated with FSH-β and LH-β respectively (r=0.530, P<0.05; r=0.538,P<0.01).In pituitary of boars, significant positive correlation was found between mRNAexpressions of AdpR1and AdpR2(r=0.852, P<0.01). GnRHR were significantlypositive correlated with FSH-β and LH-β respectively (r=0.500, P<0.05；r=0.828,P<0.01).In pituitary of gilts, significant positive correlation was found between mRNAexpressions of AdpR1and AdpR2(r=0.541, P<0.05). GnRHR were significantlypositive correlated with LH-β (r=0.517, P<0.05). The expression of AdpR2weresignificantly correlated with LH-β, GnRHR, serum FSH respectively (r=-0.507,P<0.05; r=-0.639, P<0.01; r=-0.460, P<0.05).Furthermore, The concentration of serum LH were significantly positivecorrelated with FSH (r=0.475, P<0.05), LH were significantly positive correlated withFSH in boars and gilts (r=0.569, P<0.01; r=0.396, P<0.05); The concentration ofserum LH and FSH were significantly positive correlated with the mRNA expressionof FSH-β and LH-β (r=0.403, P<0.05；r=0.376, P<0.05).Our observations indicated that the Adp may mediated by AdpR1and AdpR2inhibits secretion of FSH and LH by GnRHR or directly in pituitary.2Effect of Adp on gonadotropine synthesis in pituitary gland cells of pigs and itspossible mechanismPituitary gland cells were isolated abactcrially from pituitary at90d ofWannanhua gilts. Cells treated with rAdp48h after culture. ELISA methods were usedto detect the concentration of LH and FSH in solution, and qRT-PCR methods wereused to detect the expression of AdpR1, AdpR2, GnRHR, LH-β and FSH-β mRNA incells after4h and24h treatment of rAdp. The results showed as follows:(1) The variation of LH and FSH concentration in culture solution:LH and FSH concentration decreased significantly after the treatment of2μg/mLand10μg/mL rAdp for4h (P <0.01), there were no significant difference between them. LH and FSH concentration has no significant change after the treatment of2μg/mL and10μg/mL rAdp for24h.(2) The variation of mRNA expression of AdpRs and reproduction-related factorsin cells:AdpRl mRNA expression was significantly increased with rAdp treatment for4h(P<0.05); The expression of AdpR2mRNA had a slight increasing with rAdptreatment, but with no significantly change(P＞0.05). rAdp significantly decreased theexpression of LH-β, GnRHR (P <0.01or P <0.05), The FSH-β, AMPK mRNA haddecrease tendency with rAdp treatment for4h. AMPK mRNA decreased significantlyafter the treatment of10μg/mL rAdp for4h (P <0.05). The mRNA expressions ofAdpRs and reproduction-related factors were no significant change after the treatmentof2μg/mL and10μg/mL for24h.These results suggested that Adp may activate AMPK signaling pathwaysmediated mainly by AdpR1, then decrease GnRHR expression, and finally inhibit thesecretion of FSH and LH..