Lecture 8 Flashcards
Animal Estrogens
Sinthesis:
- Mature ovarian-follicle;
- Interstitial cells;
- Placenta;
- Sertoli cells;
- Adrenal cortex;
- Tumors;
- Ovarian cyst;
Animal Estrogens(2)
Native product:
- Estradiol
Metabolites:
- Estrone;
- Estriol;
Into the follicle linked-form and sulfuronic glucuronic acid;
In the blood, bind with plasma protein; (sex hormone-binding globulin)
The target organs, is disconnected and, after producing effect, it is metabolized.
Animal Estrogens ACTIONS:
Action on: central nervous system
- hypothalamus
- Pituitary
- Reproductive tract
- Metabolism
Action on CNS
- increases the excitability of neurons;
- regulate sexual behavior through specific peptide
- Estrus behaviour :
- Acceptance to mount mare, cow, sheep, bitch; immobility to sow.
Animal Estrogens actions on genital tract:
Action on the genital tract:
- Oviduct,
- increases muscle contractility;
- Endometrium:
- hyperemia, hyperplasia, hypersecretion:
- vessels growth
- uterine edema ;
actively proliferating cells, the endometrium becomes
pseudolayered;
stimulates secretion of mucus, translucent;
Activating immune system
Animal Estrogens indications
Products:
- Estradiol® (17-β- estradiol);
- Ginosedol® (benzoat de estradiol);
- Estrolent® (estradiol undecilat);
- Etinilestradiol® (etinil- estradiol);
- Menformon (benzoat de estradiol);
- Mesalin (benzoat de estradiol) ş.a.
Synthetic estrogens
- Stilbene derivatives (stilbestrol, diethylstilbestrol)
- Derivatives of aromatic hydrocarbons (dienestrol,hexestrol, benzestrol)
Effects:
- strong, retard effect in small doses;
- therapeutic limitations (cancerous);
- produce ovarian uterine glands cysts &;
- Recommended for cevix opening;
- recommended in cases of hypo-or agalactia;
Products:
- Sintofolin ® (di hexestrol)
- ® diethylstilbestrol (diethylstilbestrol)
Vegetal estrogens
The content of estrogen depend on:
- External factors:
- precipitation curve;
- fertilizers;
- harvest time;
- storage;
2. Genetics.
Vegetal estrogens activity
Increased estrogen activity:
- Heavy rains;
- P deficiency;
- Red clover Mowing before flowering;
- alfalfa Mowing during or after flowering;
- The third and fourth alfalfa mowing;
- Silage supplemented with molasses;
Mycetes attack;
Natural drying reduces the estrogen activity,
artificial drying keeps it.
Vegetal estrogens metabolism?
Metabolism
- after ingestion, estrogen activity may change;
- ruminal microorganisms and liver enzymes may demethylated phytoestrogens;
- biocanina A → formononetina genistein, daidzein, more active in the cow;
- genistein and p-ethylphenol biocanina A → formononetină, inactive (the sheep) &-ecvol isoflavones (estrogen-action);
- Some of the isoflavones are conjugated and excreted by the kidneys
- Cumestrol eliminating : urine and milk.
Vegetal estrogens identification ?
Biological tests in domestic animals
- Criteria: nipples lenght in male lambs, cervical mucus in castared sheep;
- Fluorimetry: formononetin, daidzein, ecvol, cumestrol;
- Radioimunoasay (most of them);
- Immunoenzymatic (ELISA: Enzyme-Linked Immuno Sorbent Assay).
*Normal components, when consumed in moderate
quantities;*
In large quantities, affect fertility.
Males:
- foreskin development
- genital infections
Effects of Phytoestrogens on Cattle.
- mammary development;
- swelling of the vulva;
- discharge of cervical mucus;
- enlargement of the uterus;
- cystic ovaries;
- irregular estrus;
- nymphomania;
- anestrous;
- cows failed to conceive to service.
- little effect on male ruminants
Vegetal estrogens Mechanisms of action:
- Adversely affect gamete transport;
- Decrease plasma levels of progesterone;
- Increase estrogen levels antepartum;
- Influences the gonadotropins secretion
Antiestrogens
Example:
genistein, cumestrolul;
Products:
Clomifen®- block restrogen receptors
Mycotoxic Estrogenic Syndrome
Mycotoxic Estrogenic Syndrome (2)
Mycotoxic Estrogenic Syndrome (3)
Mycotoxic Estrogenic Syndrome (4)
Progesterone
- Most blood progesterone, circulate free or transcortin bind, conjugated with glucuronic or sulfuric acid bodyFrom metabolic point of view, progesterone circulate in the in two isoforms (alpha and beta), with plasma proteins ;
- Plasma and milk progesterone concentrations and corpus luteum development are directly proportional;
- In the he cow, the blood progesterone is in proestrus, 0.5-1 ng / ml plasma,
- estrus decreases to 0.5 ng / ml,
- metestru (days 1-5 after ovulation),
- increased to 1.2 ng / ml,
- diestrus 6-16 days to reach 3-6 ng / ml.
Progesterone metabolism:
Progesterone: Physiological effects and biochemical functions
- CNS:
- decreases excitability produced by estrogen
- changing behavior
- Physiological effects and biochemical functions
- At the metabolic level:
- Anabolic
- generally hyperglycemic effect
- In the hypothalamus:
- Polarized neurosecretor cells → blocks the connection between the hypothalamus and pituitary
- Synthesis and accumulation of the neurosecretions and
- gonadotropins;
- The pituitary gland:
- There are a large number of gestagenic receptors
- Negative feedback on LH secretion;
- Blocks the release of gonadotropic hormones
- In the ovary:
- Antral follicle development & inhibits ovulation;
- Trophic role
In conclusion, in the genital tract, progesterone produces:
- cell hypertrophy,
- uterine hypersecretion
- Uterine quiescence
Synthetic Gestagenic hormones
- Effects:
- Controlling estrous cycle in animals
- Administered orally, parenterally, and vaginal; s.c. form implants placed;
- Blocks the hypothalamic-pituitary-ovarian axis and thus the release of FSH and LH;
- After suppression therapy, there is a massive discharge of gonadotropic hormones
- Does not block the development of follicles that endogenous estrogens may have a favorable effect on the endometrium;
Products and formulations containing the progestin
Testosteron
- Testosteron: transport
- Blood circulation linked through the α-globulin (steroid binding globulines)
- 98% bind to transport proteins
- Testosterone: receptors
- CNS link testosterone, where has partial
- estrogen effect;
- Hypothalamus;
- Pituitary;
- Male genital system;
- Accessory glands.
Testosteron: regulation
