GAD L8 (Menstrual and Ovarian Cycles)_c8f78159a14daea119c651e77c5062d6.pdf
Transcript
GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Menstrual and Ovarian Cycles Lecture 5 Level 3 Year 2 1 WRITTEN AND COMPILED BY GAD 231 COMMITTEE. ...
GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Menstrual and Ovarian Cycles Lecture 5 Level 3 Year 2 1 WRITTEN AND COMPILED BY GAD 231 COMMITTEE. GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Objectives: At the end of this lecture the students will be able to: Describe the relationship between the hypothalamus, pituitary hormones, the ovarian hormones and internal female reproductive organs during the menstrual cycle, ovulation and pregnancy 2 WRITTEN AND COMPILED BY GAD 231 COMMITTEE. GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Female cycles a GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Ovarian cycle 5 Definition : Cyclic changes in the ovaries under the effect of FSH and LH produced by the anterior pituitary gland It includes development of follicles, ovulation and corpus luteum formation P Glands GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Ovarian cycle(Cont.) Phases: Pre-ovulatory phase : Gonadotropin releasing hormone (GnRH) is released by the hypothalamus stimulating the anterior pituitary gland to secrete FSH that stimulates growth of the follicles. Tempory endocrine Ovulatory phase : Gonadotropin releasing hormone (GnRH) is released by the vary hypothalamus stimulating the anterior pituitary gland to secrete LH that stimulates ovulation. Post ovulatory phase: Corpus luteum formation that secretes progesterone. GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Menstrual cycle Definition : Is the time during which the oocyte matures, is ovulated , and enters the uterine tubes. Estrogen and progesterone(ovarian hormones) produce cyclic changes in the endometrium. Also called endometrial cycle. GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Menstrual cycle Phases: Proliferative phase : Controlled by estrogen secreted by granulosa cells. Estrogen stimulates the proliferation of endometrial stromal cells, glands and blood vessels. Secretory phase(Luteal phase) : Controlled by progesterone secreted by corpus luteum. Progesterone stimulates endometrial glands to secrete mucous secretion. GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Menstrual phase : is the bleeding phase The endometrial shedding occurs if fertilization failed. Usually lasts 4 to 5 days If fertilization does not occur: 1. The corpus luteum degenerates. 2. Estrogen and progesterone levels fall and the secretory endometrium enters the ischemic phase 3. Menstruation occurs Ischemic phase GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Fuji If fertilization occurs: Cleavage of the zygote and blastogenesis (formation of blastocyst) begins. HCG The blastocyst implants in the endometrium Human chorionic gonadotropin hormone keeps the corpus luteum secreting estrogen and progesterone The luteal phase continues and menstruation does not occur. Pregnancy phase GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Ovulation: GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH After rupture GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH After rupture GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH After rupture GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH After rupture GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Fertilization GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Fertilization GROWTH, DEVELOPMENT & AGING COLLEGE OF MEDICINE GAD 231 AL-FARABI COLLEGES IN RIYADH Reference Book: The Developing Human Clinically Oriented Embryology Keith L. Moore, T.V.N. Persaud and Mark G. Torchia 9th Edition 2013 ISBN: 978-1-4377-2002-0 www.elsevier.com/permissions. 18 WRITTEN AND COMPILED BY GAD 231 COMMITTEE.
