Dihydropyridine was first discovered by the former Soviet Union. At that time, it was only used as an antioxidant in animal and vegetable oils to prevent oil rancidity. It was not until the 1970s that dihydropyridine was found to not only have antioxidant effects, but also promote the growth of livestock and poultry.
Do you really understand the functions of dihydropyridine? Physiological functions of dihydropyridine
1 Antioxidant effect
Valdman et al. (1977) reported that dihydropyridine can reduce vitamin A, β-carotene, etc. in feed Oxidative loss of nutrients, thereby increasing their utilization. Dihydropyridine can affect the composition of biomembrane lipids, increase the activity of 6-phosphate glucose enzyme in biomembranes, stabilize membrane proteins and binding enzymes to maintain the normal structure and function of the cell membrane system, and also increase serum superoxide dismutase (SOD) activity (Fang Xingtang et al., 2002). SOD is a scavenger of superoxide free radicals (O2-) in the body. O2- not only destroys the normal functions of cells, but also causes chain reactions to produce other free radicals. These free radicals can cause lipid peroxidation of long-chain unsaturated fatty acids on the egg cell membrane, resulting in increased membrane permeability and membrane The upper receptor is inactivated, causing follicle atrophy. Increased SOD activity can prevent chain reactions caused by free radicals, inhibit the peroxidation process of lipid compounds, protect cell surface receptors and organelles, and maintain the integrity of biological membranes (Piakova, 1986).
2. Increase the levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
Dihydropyridine can significantly increase the levels of FSH and LH in the pituitary gland and serum. FSH mainly acts on the granulosa cells of the ovary, promoting the absorption of amino acids by the granulosa cells, thereby promoting the growth and maturation of follicles and the growth and proliferation of ovarian granulosa cells, and inhibiting the occurrence of follicle atrophy. At the same time, FSH may also increase the biological activity of IGF-1 and promote protein synthesis by regulating the insulin-like growth factor (IGF)-binding protein transcription process. When follicles develop to a certain stage, FSH can promote the granulosa cells of antral follicles to produce LH receptors and induce the secretion of LH. LH can increase the cyclic adenosine monophosphate (cAMP) content and the number of progesterone receptors on the granulosa cells of mature follicles. LH cooperates with FSH to promote follicle growth and development, and at the same time stimulates mature follicle granulosa cells to release progesterone and stimulate ovulation. Therefore, dihydropyridine promotes follicle development and ovulation by stimulating the secretion and release of FSH and LH, effectively inhibits the occurrence of follicular atresia and increases the number of effective egg cells.
3. Increase the content of cyclic adenosine monophosphate in the hypothalamus and adenohypophysis.
Dihydropyridine increases the cAMP content in the hypothalamus by protecting the arcuate nucleus cell membrane of the hypothalamus. cAMP is the second messenger in cells and can promote the release of gonadotropin-releasing hormone (GnRH). . In addition, after GnRH binds to specific receptors on the granulosa cells of the adenohypophysis, it activates the adenylyl cyclase (AC)-cAMP-protein kinase (PK) system of the adenohypophysis, thereby increasing the activity of aromatase in the granulosa cells and promoting The conversion of androgens into estrogens increases the amount of estradiol. cAMP can also directly enter the cell nucleus and bind to its receptor protein, activating the DNA transcription process, thus promoting the development and ovulation of follicles, and effectively inhibiting the occurrence of follicular atresia. cAMP itself is also an important regulatory factor in the process of mRNA production, which regulates a variety of Protein synthesis plays an important regulatory role.
4. Reduce the cortisol content in serum and improve the body’s immune function.
Dihydropyridine can cause a downward trend in serum cortisol concentration. The hydroxylase system in the process of cholesterol metabolism and conversion to corticosteroids requires reduced coenzyme II (NADPH), cytochrome P450 and molecular oxygen as the electron transfer system in its enzymatic reaction. Dihydropyridine can combine with NADPH-specific electron transport chain terminal oxidase cytochrome P450 to form a complex, thereby inhibiting the activity of hydroxylase and limiting the synthesis and secretion of cortisol by the adrenal gland. Cortisol can promote the decomposition of proteins in extrahepatic tissues, especially muscle tissues, and at the same time inhibit the synthesis of nucleic acids within cells, thereby affecting protein synthesis. Glucocorticoids are recognized immunosuppressants, especially cortisol, which can inhibit the growth of the bursa of Fabricius in chicks and have a similar effect on the thymus. Moreover, dihydropyridine can increase the T3 concentration in the blood and reduce the cortisol concentration, thereby improving the body’s immune function of pyrithione.
5. Improve the reproductive function of livestock and poultry
Improve sperm quality. Dihydropyridine is a natural vitamin E-like substance that has some functions of natural vitamin E. By protecting vitamin A, β- Carotene and vitamin E regulate the secretion of gonadal hormones from the anterior pituitary gland, promote the development and growth of the reproductive system, and maintain its normal physiological functions.
Do you really understand the function of dihydropyridine? Clinical application of gain speed (5% dihydropyridine)
1. Boars
Gain speed 2kg/ton of feed, long-term addition, can increase the growth rate of boars Semen quality, reduce sperm deformity rate, increase boar ejaculation volume (50-100ml), gain rate 3kg/ton + Weixi (25% vitamin C) 500g/ton, use for 7-10 days, treat dead semen and semen of boars Small amount and poor sperm motility.
2. Sows, especially gilts
Used one month before breeding, the gain rate is 3kg/ton, and used for 1 month, it can improve the estrus of gilts. The breeding rate and breeding rate increase the number of litters by more than 1 per litter on average.
3. Lactating sows
Gain rate 3kg/ton + Weixi (25% vitamin C) 500g/ton,Start using it in the first seven days until weaning, which can increase the sow’s milk production and increase the birth weight and weaning weight of piglets.
4. Fattening pigs
The gain rate is 2 kg/ton. Long-term addition can increase daily weight gain and lean meat rate.
