Induction of Osteoporosis by Ovariectomy in
Adult Albino Rats
Fatma E El Safty, Mostafa M El Habeby, Abeer E El mehi, Neveen M El sherif and Eman A Essa*
Department of Anatomy and Embryology, Menoufia University, Egypt
Submission: March 20, 2018; Published: April 06, 2018
*Corresponding author:Eman Abd El-ghani Essa Ebrahim, Department of Anatomy and Embryology, Faculty of Medicine, Menoufia University, Shebin El-Kom City, Menoufia Governate, Egypt, Tel: 002-01010440442; Email: firstname.lastname@example.org
How to cite this article: Fatma E El S, Mostafa M El H, Abeer E El m, Neveen M El s, Eman A E. Induction of Osteoporosis by Ovariectomy in Adult Albino
Rats. Anatomy Physiol Biochem Int J: 2018; 4(4): 555648. DOI: 10.19080/APBIJ.2018.04.555648.
Objectives: To evaluate the deterioration of bone tissue in the ovariectomized adult albino rat, as a model of postmenopausal osteoporosis.
Data Sources:Medline databases (PubMed, Medscape, Science Direct) and all materials available in the internet from 2009 to 2015.
Study Selection:The initial search presented 11 articles where 5 had inclusion criteria. The articles studied the efficacy of ovariectomy on bone of adult rats.
Data Extraction: If the studies not meet the inclusion criteria, they were excluded.
Data Synthesis:omparisons were made by structured review with the results tabulated. Each study was reviewed independently and the obtained data were rebuilt in new language according to the need of the researcher and arranged in topics through the article.
Findings: In total 5 potentially relevant publications were included, all were animal studies. The studies indicate the deterioration of bone state following ovariectomy.
Conclusion: Decreased estrogen level following ovariectomy causes osteoporosis.
Keywords: Bone; Estrogen; Osteoporosis; Ovariectomy; Rat
Abbrevations: BMD: Bone Mineral Density; ALP: Alkaline Phosphatase; P: Phosphorus; CA: Calcium
Osteoporosis is a progressive bone disease characterized by a decrease in bone mass that leads to an increased risk of fracture. In osteoporosis, the bone mineral density (BMD) is reduced, bone micro architecture deteriorates, and the amount and variety of proteins in bone are altered . The risk of developing osteoporosis increases with age and is four times higher in women than in men. In osteoporosis, the rapid decline in endogenous estrogen production that occurs during menopause results in a significant increase in bone turnover which results in significant bone loss and increased risk for fragility fracture . Ovariectomy is one of the most common surgical operations in women throughout the world. Ovariectomy results in increased rate in bone resorption outweigh the increased rate of bone formation. Consequently, this leads to osteoporosis . The overall objective is to determine the deterioration on bone tissue in the ovariectomized adult albino rat model of osteoporosis.
Search Strategy: We reviewed papers on the impact of ovariectomy on osteoporosis from Medline databanks which
are (PubMed, medscape and Science Direct) and also materials accessible in the Internet. We used ovariectomy / osteoporosis /bone rat as searching codes. The search was accomplished in the electronic databanks from 2009 to 2015.
Study Selection: All the researches were freely evaluated for addition. They were added if they contented the following criteria:
Inclusion criteria of the published studies:
1. Published in English language.
2. Published in peer-reviewed journals.
3. Focused on osteoporosis.
4. Discussed the relation between osteoporosis and ovariectomy with decreased estrogen.
5. If a study had several publications on definite viewpoints we used the most recent publication giving the most related data.
Data Extraction: If the studies did not achieve the above
criteria, they were omitted such as report without peerreview,
not within federal studies platform, letters/ comments/
editorials/ news and studies not focused on the effect of
ovariectomy on osteoporosis in adult rats.
Quality Assessment: The quality of all the studies was
assessed. Important factors included, study design, attainment
of ethical approval, evidence of a power calculation, specified
eligibility criteria, appropriate controls, and adequate
information and specified assessment measures. It was expected
that confounding factors would be reported and controlled for
and appropriate data analysis made in addition to an explanation
of missing data. It was expected that confounding factors would
be reported and controlled for and appropriate data analysis
made in addition to an explanation of missing data.
Data Synthesis: A designed systematic review was
accomplished with the outcomes formulated.
In total 11 potentially related publications were recognized,
6 articles were eliminated. A total of 5 studies were included in
the review as they were considered suitable by forthright the
containment criteria. All were animal researches. The majority
of the researchers surveyed the outcomes of ovariectomy on
If the researches did not accomplish the above criteria, they
were omitted such as commentary without peer-review, not
within federal studies platform, letters/ comments/ editorials/
update and researches not concentrated on the effect of
ovariectomy on osteoprosis.
The considered publications were assessed to evidencebased
medicine (EBM) criteria by means of the classification
of the U.S. Preventive Services Task Force & UK National Health
Service protocol for EBM in addition to the Evidence Pyramid.
U.S. Preventive Services Task Force:
1. Level I: Evidence obtained from at least one properly
designed randomized controlled trial.
2. Level II-1: Evidence obtained from well-designed
controlled trials without randomization.
3. Level II-2: Evidence obtained from well-designed
cohort or case-control analytic studies, preferably from
more than one center or research group.
4. Level II-3: Evidence obtained from multiple time
series with or without the intervention. Dramatic results
in uncontrolled trials might also be regarded as this type of
5. Level III: Opinions of respected authorities, based on
clinical experience, descriptive studies, or reports of expert
Vital issues encompassed, study design, fulfillment of
ethical approval, evidence of a force estimation, definite
eligibility norms, and suitable controls, enough data and definite
assessment manners were evaluate:
Four studies (Table 1) [4-7] cited that ovariectomy highly
deteriorates the histological features of bone with decreased
thickness of both compact and cancellous bone together with
decreased collagen in bone matrix.
Three studies (Table 1) [5,7,8] revealed that ovariectomy
causes marked biochemical changes as decreased serum calcium
(CA) and phosphorus (P) level together with increased serum
alkaline phosphatase (ALP) levels.
The present study was achieved to assess the effect of
ovariectomy on rat bone. Bone is a dynamic tissue and its
metabolism is maintained by a balance between osteoblastic
bone formation and osteoclastic bone resorption. If this balance
was disturbed, bone mass gradually lost causing osteoporosis
. Ovariectomy is the surgical removal of an ovary or ovaries
in laboratory animals. In human this operation is called
oophorectomy. Ovariectomy has been used as a method to induce
estrogen deficiency which is similar to the postmenopausal
women in that there is a rapid loss of trabecular bone mass
and strength that occur shortly after ovariectomy . The
morphological and histological changes in bones of osteoprotic
rats after ovariectomy were a result of marked estrogen
deficiency and impaired calcium absorption leading to marked
resorption of bone with less bone formation causing marked
thinning of both cortical and cancellous bony trabeculae with
marked trabecular discontinuity . Liu, et al.  concluded
that decreased estrogen causes increased parathyroid hormone
level, which might affect osteoclasts formation and disrupt bone
resorption. This was in contrast with the study on the fluoride
induced osteoporosis in which there was increased thickening
of bone trabeaculae in osteoprotic rats due to increased osteoid
formation and bone deposition .
Sohair, et al.  stated that, following ovariectomy there was
serum calcium and phosphorus deficiency caused by decreased
calcium absorption and incomplete mineralization of bone, this
lead finally to decrease in bone mineral density (BMD). This was
caused by hyperparathyroidism secondary to calcium deficiency
and exacerbated by estrogen deficiency. Mansur & Wojciech
 results showed that hypoestrogenism after ovariectomy
causes characteristic increase in the bone turnover markers
(alkaline and acid phosphatases) in serum of experimental
animals. Lack of inhibiting activity of estrogen on osteoclasts
caused the increase in acid phosphatase activity and increase in
bone resorption. Together with increased resorption processes,
bone formation process was also increased by enhancement of
osteoblast activity ledding to growth of alkaline phosphatase