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PubMed1985

Early onset of tetany following thyroidectomy: report of two cases.

The most common complication of total thyroidectomy is hypocalcemia. Following thyroidectomy, especially total thyroidectomy, the serum calcium usually falls gradually and patients do not usually require supplementary medication before 24 hours. Two cases of total thyroidectomy are presented in which the preoperative serum calcium levels were normal and hypocalcemic tetany developed in the recovery room immediately after the operation. The hypocalcemia was a temporary phenomenon, and neither patient requires supplementary calcium at the present time. There is no good explanation for this precipitous drop in the serum calcium levels in these two patients.

Adult↗
PubMed1999

Time of thyroidectomy variably affects seasonality in female American tree sparrows (Spizella arborea).

Female American tree sparrows (Spizella arborea) were injected with Na131I before, at, or after the onset of photostimulation in order to study the effect of time of thyroidectomy on three components of seasonality: thyroid-dependent photoperiodic ovarian growth, photorefractoriness, and postnuptial (prebasic) molt. Thyroidectomy before or at the onset of photostimulation abolished all components of seasonality; birds exhibited only minor thyroid-independent photoperiodic ovarian growth. Thyroidectomy on day 7 of photostimulation blocked the transition from photosensitivity to photorefractoriness; although birds showed thyroid-dependent photoperiodic ovarian growth, they neither exhibited ovarian regression nor initiated postnuptial molt. Thyroidectomy on day 14, 21, or 28 of photostimulation had no remarkable effect on any component of seasonality. We conclude that separate mechanisms control photoperiodic ovarian growth and photorefractoriness/molt and that, early during photostimulation, the thyroid has a codependent role in programming female tree sparrows for vernal as well as autumnal seasonal events.

Animals↗
PubMed2002

Autoimmune thyroid disease accompanied by recurring episodes of painful thyroid ameliorated by thyroidectomy.

A 71-yr-old female initially presented with clinical and biochemical hyperthyroidism with high TSH binding inhibitory immunoglobulin (TBII) and anti-thyroid peroxidase antibody (TPOAb) titers. Histological findings of the thyroid revealed hyperplasia with a focal germinal center, indicating Graves' disease and mild focal chronic thyroiditis. Four episodes of painful and tender thyroid occurred over the next 2 yr accompanied by acute inflammatory reactions. The first episode that developed while the patient was in a hyperthyroid state was soon followed by hypothyroidism associated with further increases in anti-thyroglobulin antibody (TGAb) and TPOAb titers. The subsequent 3 episodes occurred during the hypothyroid state, when the TGAb titer progressively increased with each episode. We performed subtotal thyroidectomy to prevent further episodes. Specimens obtained at thyroidectomy showed that extreme fibrosis had replaced the thyroid parenchyma with collapsed follicles and moderate lymphocyte infiltration. No further episodes occurred after thyroidectomy, and during a 3-yr follow-up period, TBII and thyroid-stimulating antibody (TSAb) disappeared and TGAb and TPOAb titers decreased. This case report provides further evidence supporting the notion that thyroid epithelial destruction progresses during relatively short periods of recurrent painful thyroid and that thyroidectomy helps patients affected by this condition that are unresponsive to other treatment strategies.

Aged↗
PubMedDate not supplied

Gamma probe-guided surgery for revision thyroidectomy: in comparison with conventional technique.

Reoperative thyroid surgery may be required in patients who undergo any procedure less than total or near total thyroidectomy. The aim of this study was to investigate advantages of gamma-probe guided revision thyroidectomy (GGRT) over conventional revision thyroidectomy (CRT) in patients with differentiated thyroid carcinoma (DTC). GGRT was assessed according to the TSH values, complication rates and the incidence of carcinoma in residual thyroid tissue. In this randomised prospective clinical trial, 25 patients with differentiated thyroid carcinoma who had previously undergone surgery for benign multinodular goiter were included in the study. GGRT was performed in 11 (44%) patients (Group 1) and CRT in 14 (65%) (Group 2). The intraoperative mean ratio of thyroid activity to background activity (T/B) was detected as 5.1 +/- 1.4 and the mean ratio of thyroid bed activity to background activity after excision (Tbed/B) was 1.3 +/- 0.3, (p < 0.01). Although the incidence of carcinoma in residual thyroid tissue was higher in group 1 (4/11) in comparison to group 2 (1/14), it was not statistically significant. The elevation of the TSH concentration at the first post-operative month was significantly higher in group 1 in comparison with group 2 (18 +/- 25 5 +/- 3 mlU/l), (p < 0.02). These results indicate that intraoperative gamma probe application may be beneficial to detect and remove residual thyroid tissue in revision thyroidectomy.

Adult↗
PubMed1999

Postoperative changes in thyrotropin-binding inhibitory immunoglobulin level in patients with Graves' disease: is subtotal thyroidectomy a suitable therapeutic option for patients of childbearing age with Graves' disease?

Thyroid-stimulating hormone (TSH)-binding inhibitory immunoglobulin (TBII) is thought to be one of the essential causes of Graves' disease, and most cases of neonatal hyperthyroidism can be explained by transplacental passage of TBII. Because surgery is often indicated for patients of childbearing age, it is important to elucidate how surgery reduces TBII levels. Between 1988 and 1991 a total of 946 female patients with Graves' disease underwent subtotal thyroidectomy. Follow-up examination was undertaken at 1, 2, 3, and 4 to 5 years after surgery. At 4 to 5 years after surgery, 76.8% of patients without recurrent overt hyperthyroidism had TBII < 20%. In patients with recurrent hyperthyroidism, TBII increased gradually during follow-up, and they had higher TBII levels than nonrecurrence patients. There were a few euthyroid and hypothyroid patients who had TBII > 60%, and the number of such patients decreased annually. In most of the patients, immunologic remission was obtained by subtotal thyroidectomy except for their having recurrent hyperthyroidism. To acquire immunologic remission, hormonal remission, at least, would be necessary. Because no definite factor other than the size of the thyroid remnant related to postoperative thyroid function was elucidated, near-total thyroidectomy rather than subtotal thyroidectomy is expected to be induced not only hormonal remission but also immunologic remission. It should be noted that a few patients achieved hormonal remission but not immunologic remission.

Adult↗
PubMed2003

Utilization of fine-needle aspiration in patients undergoing thyroidectomy at two academic centers across the Atlantic.

Although fine-needle aspiration (FNA) has been accepted as a first-line test in patients with thyroid masses, the utilization of FNA varies even among experienced surgeons. To determine its utility we compared FNA results, pathology, and clinical results in patients who underwent thyroidectomy in two major endocrine centers on both sides of the Atlantic: one in the United States (US) and another in the United Kingdom (UK). Between January 1997 and March 1998 a total of 84 patients underwent thyroid surgery at the UK center, and 143 underwent thyroidectomy at the US center. The most common indication for thyroidectomy at the UK center was compressive goiter (CG), whereas follicular neoplasm (FN) was the most common indication at the US center. Bilateral thyroid resections, frozen section utilization, and thyroid cancer surgery were more common at the US center. Thyroidectomy for symptomatic multinodular goiter and Graves' disease was more prevalent at the UK center. Thyroid gland weights were also significantly greater in the UK, indicating a higher incidence of endemic goiter. FNA was more commonly employed in the US center (84% vs. 52%; p < 0.001). Despite the differing utilization of FNA at these major endocrine centers, only one thyroid cancer at each institution was not detected preoperatively (both patients had a benign FNA result). Therefore there were no clinically significant thyroid cancers found in patients who did not undergo preoperative FNA. In conclusion, FNA appears to be differentially utilized depending on the incidence of endemic goiter, Graves' disease, and thyroid cancer. In this series no clinically significant thyroid cancers were found in patients who did not undergo preoperative FNA. Therefore in the hands of experienced thyroid surgeons, FNA can be utilized selectively based on the clinical presentation.

Biopsy, Needle↗
PubMed2004

Gasless video-assisted total thyroidectomy in the treatment of low risk intrathyroid papillary carcinoma.

Video-assisted thyroidectomy, although an increasingly used method to treat benign thyroid nodules, is rarely used to treat thyroid cancer. We performed gasless video-assisted total thyroidectomy for the treatment of papillary carcinoma of the thyroid. The patients were two men and five women with ages ranging from 29 to 52 years (median 35 years). Tumor size ranged from 0.7 to 3.8 cm (median 1.8 cm). The remnants of functional thyroid tissues were ablated with 1110 MBq of 131I following total thyroidectomy. One year after radioiodine ablation uptake of 74 MBq 131I shown by scintigraphy ranged from 0.29% to 0.70% (median 0.57%), and the serum thyroglobulin level was less than 1 microg/L. No perioperative complications occurred. The follow-up period ranged from 1 year 5 months to 3 years 7 months (median 2 years 10 months). In conclusion, gasless video-assisted total thyroidectomy is a feasible means for treating relatively small, non-invasive, clinically solitary, differentiated thyroid carcinomas.

Adult↗
PubMed2004

Risk factors for recurrent nodular goiter after thyroidectomy for benign disease: case-control study of 244 patients.

Surgery for recurrent nodular goiter is associated with a significant risk of parathyroid and recurrent laryngeal nerve (RLN) morbidity. Total thyroidectomy for benign disease is assessed. The aim of this study was to evaluate the risk factors for recurrence and the morbidity associated with reoperation. From 1969 to 1996 a total of 4334 thyroidectomies were performed, of which 122 were for recurrent nodular goiter (group I: 116 women, 6 men). A matched case-control study of 122 patients operated on for nonrecurrent multinodular goiter was performed (group II: 112 women, 10 men). Age, family history, initial surgery, pathology, and morbidity were compared in the two groups by chi2 test, Fisher's exact test, and the Mantel-Haenszel test. The mean age was 39.88 years in group I and 47.89 years in group II. There was no statistical difference in relation to the extent of thyroidectomy or morbidity after initial surgery. Statistical differences were identified regarding age (p = 0.000002) and the multinodular nature of the initial goiter (p = 0.005). Bilaterality and family history were less significant (p = 0.09 andp = 0.08, respectively). Temporary RLN palsy and temporary hypoparathyroidism were higher in group I (12.3% vs. 5.7%,p = 0.0737; 10.6% vs. 1.7%, p = 0.00337). Permanent RLN palsy was found in 0.8% in group I and in none in group II (p = 0.5, NS). Young age and multiple nodules at initial surgery are risk factors for recurrence. A higher rate of temporary morbidity was demonstrated after surgery for recurrent goiter. Total thyroidectomy for multinodular goiter is advisable.

Adolescent↗
PubMed2006

Hypocalcaemia and parathyroid hormone assay following total thyroidectomy: predicting the future.

BACKGROUND: Ambulatory surgery (23:59-hour hospital stay) is gaining popularity in endocrine surgery. Hypocalcaemia is common following total thyroidectomy. Identifying patients with low risk of hypocalcaemia may facilitate early discharge (24-hour stay). METHODS: We conducted a prospective study including all patients undergoing total thyroidectomy. Blood samples were taken immediately following skin closure and the following morning for parathyroid hormone (PTH) and calcium measurement. Calcium supplements were routinely given when serum calcium was below 2.0 mmol/l. RESULTS: Thirty patients (27 females, 3 males) underwent total thyroidectomy (including 4 nodal dissection) for multinodular goitre (14), Graves' disease (11), papillary (4) and follicular (1) thyroid carcinoma. Twelve patients developed symptomatic transient hypocalcaemia. Based on morning calcium of < 2.0 mmol/l as trigger for calcium supplementation, 8 patients received calcium supplement with 4 false negatives, resulting in a specificity of 94.4%, sensitivity of 66.7%, positive predictive value (PPV) of 88.9% and negative predictive value (NPV) of 81%. Based on PTH levels (< 1.5 pmol/l) immediately following skin closure, 11 patients would receive calcium supplement, with 1 false negative resulting in a specificity of 83.3%, sensitivity of 91.7%, PPV of 78.6% and NPV of 93.8%. If supplementation is based on PTH levels (< 1.5 pmol/l) immediately following skin closure and morning calcium level (< 2.0 mmol/l), all 12 symptomatic patients will be correctly treated, with 4 false positives resulting in a combined specificity of 77.8%, sensitivity of 100%, PPV of 75% and NPV of 100%. CONCLUSIONS: Combining the immediate postoperation PTH levels (< 1.5 pmol/l) and morning serum calcium (< 2.0 mmol/l) can accurately identify patients at risk of hypocalcaemia following total thyroidectomy, allowing safe, early discharge.

Adolescent↗
PubMed2005

Use of ligasure in thyroidectomy procedures: results of a prospective comparative study.

The thyroidectomy procedure requires many manupulations to achieve prompt hemostasis. This study assessed whether the outcomes of thyroidectomy using the Ligasure electrothermal vessel sealer were comparable with the conventional suture-ligation technique. We prospectively evaluated 58 consecutive patients who underwent thyroidectomy. Patients were allocated into two groups according to their preference. There were 30 patients in the Ligasure group and 28 patients in the conventional surgery group. Complications, operating time, and hospital stay were compared between the two groups and suture-ligations performed in the Ligasure group were recorded. The age, sex, and indications were similar in the two groups (p > 0.05). Complication rates and hospital stays did not show any difference according to the techniques used. Operating time was shorter in the hemithyroidectomy and total thyroidectomy patients of the Ligasure group (mean +/- SD: 77.38 +/- 13.71 vs. 99.80 +/- 12.53 minutes, p = 0.005; and 102.50 +/- 16.69 vs.128.89 +/- 19.74 minutes, p = 0.010). The mean +/- SD number of suture-ligations for each patient in the Ligasure group was 1.83 +/- 2.12. Thyroid surgery using the Ligasure is safe, and its complication rates are comparable to these found with the conventional surgical technique. Use of the Ligasure during hemithyroidectomy and total tyhroidectomy operations provides a significantly shorter operating time.

Adult↗
PubMed2000

Total thyroidectomy for management of thyroid disease.

Total thyroidectomy is a logical treatment for many patients with thyroid disease, including patients in whom the pathologic process requiring surgery involves both lobes of the thyroid or the risk of recurrence is a significant consideration, as in benign multinodular goiter, Graves' disease, and cancer. In earlier times the risks of extensive surgery and problems of adequate hormone replacement deterred surgeons from performing total thyroidectomy. However, as we enter the twenty-first century we are confident that the technical aspects of safe total thyroidectomy are established and that thyroid hormone replacement and monitoring are readily available and accurate. In the future total thyroidectomy is likely to be performed increasingly commonly for both benign and malignant disease.

Humans↗
PubMed2001

Total thyroidectomy for benign thyroid disorders in an endemic region.

Total thyroidectomy is increasingly being accepted as a treatment of choice for differentiated thyroid cancer. However, because of presumed increased morbidity associated with this procedure, it is still not considered a viable option for management of benign thyroid disorders. To assess the safety and efficacy of total thyroidectomy for management of benign thyroid disorders, we analyzed our data from 127 total thyroidectomies performed for benign thyroid disorders. Demographic details, biochemical findings, indications for operation, specimen weight, and complications were noted. Among these patients, 52 had a toxic goiter and 75 had a nontoxic goiter. The mean duration of the goiters being present was 6.08 +/- 6.06 years (0.9--26.0 years), and the mean weight of the specimens was 136.88 +/- 120.68 g. The incidence of occult malignancy was 6.3% (n = 8), and those of permanent hypothyroidism and permanent recurrent laryngeal nerve palsy were 1.6% and 0.8%, respectively. Total thyroidectomy should be considered a treatment of choice for multinodular goiter and Graves' disease in a setting of palpable nodule(s) or ophthalmopathy (or both). It is particularly relevant in endemic regions where patients present with a long-standing, large nodular goiter with virtually no normal thyroid tissue. Reoperation for recurrent goiter in such a setting would be fraught with distressing complications.

Adult↗
PubMed2001

Post-thyroidectomy superior laryngeal nerve injury.

Voice dysfunction after thyroidectomy may be caused by damage to laryngeal nerves or lesions to strap muscles with laryngo-tracheal movement impairment. Injury to an external branch of the superior laryngeal nerve (EBSLN) is sometimes difficult to recognize clinically and its electromyographic incidence ranges from 0% to 58%. In this study we evaluated, 12-18 months postoperatively, 45 patients who had undergone thyroid surgery (6 total lobectomy, 5 subtotal thyroidectomy, and 34 total thyroidectomy), using a subjective interview, laryngeal videostroboscopy and spectrographic analysis with a multidimensional voice program. Vocal parameters included fundamental frequency, jitter, shimmer, noise-to-harmonic-ratio (NHR) and degree of sub-harmonics. Laryngeal electromyography (LEMG) of the cricothyroid (CT) muscles was performed in 21 subjects with voice problems (35 EBSLNs) using a modified method for the CT recording. In 3 patients of this group (14%) LEMG documented a unilateral EBSLN injury. Easy voice fatigue and decreased pitch range were the most common symptoms after surgery. Average values of vocal parameters pre- and postoperatively in patients without neural damage (n = 42) were: jitter 0.64% and 0.78%, shimmer 3.25% and 3.54%, and NHR 0.12% and 0.13%, respectively (P > 0.05). Acoustic analysis revealed altered patterns in some patients with no objective evidence of damage to EBSLNs, suggesting an extralaryngeal cause of vocal dysfunction, such as laryngo-tracheal fixation or lesions to strap muscles. We conclude that laryngeal videostroboscopy and spectrographic analysis are very useful to assess voice problems after thyroidectomy, including in patients without LEMG-proven neural lesions, in order to suggest early speech rehabilitation, especially in professional voice users.

Adult↗
PubMed2006

Video-assisted thyroidectomy: report of a 7-year experience in Rome.

BACKGROUND AND AIMS: We report on our series of patients selected for video-assisted thyroidectomy (VAT) over a 7-year period. MATERIALS AND METHODS: VAT is a gasless procedure performed under endoscopic vision through a single 1.5-2.0 cm skin incision. The eligibility criteria are thyroid nodules < or =35 mm, thyroid volume <30 ml, and no previous conventional neck surgery. Small, low-risk papillary thyroid carcinomas (PTC) were considered eligible. RESULTS: There were 521 VATs attempted. Conversion was necessary six times (difficult dissection in one case, large nodule size in three, and gross lymph node metastases in two). Thyroid lobectomy was successfully accomplished in 113 cases, total thyroidectomy in 398, and completion thyroidectomy in 14. In 66 patients, the central neck nodes were removed through the same access. Pathology showed benign diseases in 313 cases, PTC in 187, and medullary microcarcinoma in 1. Postoperative complications included 9 transient recurrent nerve palsies, 73 transient hypocalcemias, 3 definitive hypoparathyroidisms, 1 postoperative haematoma, and 2 wound infections. The cosmetic result was excellent. In patients with PTC, no evidence of recurrent disease was shown. CONCLUSIONS: The indications for VAT are still limited. Nonetheless, in selected patients, it seems a valid option for thyroidectomy and even preferable to conventional surgery because of its significant advantages, especially in terms of cosmetic result.

Adolescent↗
PubMed2003

Video-assisted thyroidectomy for papillary thyroid carcinoma.

BACKGROUND: In patients with small papillary thyroid carcinomas (PTC), we evaluated the operative feasibility and safety of video-assisted thyroidectomy (VAT) and the completeness of the surgical resection. METHODS: Video-assisted thyroidectomy was attempted in 24 patients with thyroid malignancy. Total thyroid resection for PTC was achieved completely by VAT in 20 of them, who were included in this study. RESULTS: In this study, 12 total thyroidectomies and 8 lobectomies followed by completion thyroidectomies were performed. Eight patients also underwent central neck lymph node dissection. Mean postoperative serum thyroglobulin was 0.2 ng/ml for patients receiving LT4 suppressive treatment and 4.2 ng/ml for patients after LT4 withdrawal. Postoperative ultrasonography showed no residual thyroid tissue. The mean radioiodine uptake at postoperative scintiscan was 2.2%. CONCLUSIONS: In the case of PTC, VAT is feasible and safe. The completeness of the surgical resection seems comparable with that reported for conventional surgery. Nevertheless, larger series and longer follow-up evaluation are necessary for definitive conclusions to be drawn about its oncologic validity.

Adult↗
PubMed2001

Minimally invasive video-assisted approach for partial and total thyroidectomy: initial experience.

BACKGROUND: We report our initial experience with partial and total thyroidectomy using a video-assisted approach. The feasibility, safety, and potential benefits of this technique are examined. METHODS: Between January and May 2000, 28 patients were select to undergo a thyroid lobectomy (n = 17) or total thyroidectomy (n = 11) by a video-assisted cervical approach. Patient selection was based on clinical examination and preoperative ultrasonography. The surgical procedures were conducted under general anesthesia through a minimal substernal skin incision. Frozen sections were examined peroperatively in all cases. RESULTS: The initial diagnosis was solitary nodule in 19 patients and multinodular goiter in 8 patients. One patient was treated for hyperthyroidism. The mean cranio-caudal axis and transverse diameter of the resected specimen were 4.9 +/- 0.9 and 2.7 +/- 0.5 cm, respectively, and the mean total lobar weight was 11.9 +/- 5.5 g. Conversion to conventional surgery was required in three patients (10.7%), due to local bleeding in all cases. The mean operative times were 150 +/- 8.2 and 102.5 +/- 17 min for total and partial thyroidectomy, respectively. The laryngeal nerve was identified in 94.8% of cases. The mean length of skin incision was 25.4 +/- 2 mm. There was one case of postoperative hypocalcemia and one case of postoperative hoarseness. One patient had a transient vocal cord palsy. The postoperative hospital stay was 1 day for 66.7% of patients. The pain intensity evaluation, performed on postoperative day 1 using the visual analogue scale (VAS) method, was 1.9 +/- 1.4. CONCLUSION: Video-assisted thyroidectomy is feasible, safe, and effective in selected cases. Benefits for the patients in terms of postoperative pain, hospital stay, and cosmesis still need to be assessed in a prospective trial comparing standard open and video-assisted approaches.

Adult↗
PubMed1978

The effect of castration, thyroidectomy and haloperidol upon the turnover rates of dopamine and norepinephrine and the kinetic properties of tyrosine hydroxylase in discrete hypothalamic nuclei of the male rat.

Adult male rats were either castrated, thyroidectomized, or treated with haloperidol and the rates of turnover of dopamine (DA) and norepinephrine (NE) in the median eminence (ME), the arcuate and dorsomedial nuclei of the hypothalamus were estimated from the rate of decay of DA and NE concentrations as determined by radioenzymatic assay following blockade of catecholamine synthesis by alpha-methyl-p-tyrosine. The ME of animals similarly prepared was also examined for changes in the total activity and kinetic properties of tyrosine hydroxylase (TH). Four days following the administration of haloperidol (400 microgram/kg) or 10 days after castration, there was a significant increase in the rate of turnover of DA but not NE in the ME accompanied by an increase in the Vmax but not Km for the substrate or cofactor of TH. Furthermore, the administration of haloperidol to hypophysectomized rats also significantly increased the TH activity in the ME, indicating that such changes may occur independently of any changes in serum prolactin levels. Ten days after thyroidectomy, or three weeks after treatment with prophylthiouracil, there was a significant increase in the turnover rate of DA in both the ME and dorsomedial nucleus but not in the arcuate nucleus. No changes in the turnover rates of NE in any of the three areas were observed following thyroidectomy. In the ME, the increase in turnover of DA was accompanied by an increase in the total TH activity (Vmax) as welll as a decrease in Km for tetrahydrobiopterin but not tyrosine. From these results 4 conclusions were drawn: (1) following halperidol, castration, and thyroidectomy there are increases in the activity of dopaminergic terminals within the ME; (2) castration, haloperidol and thyroidectomy may influence the activity of dopaminergic terminals within the ME by different mechanisms; (3) changes in tyrosine hydroxylase and turnover of catecholamines within the ME may occur independently of changes in prolactin levels; and (4) local recurrent afferent circuits may exist in the arcuate nucleus region of the hypothalamus.

Animals↗
PubMed1995

Thyroidectomy does not alter hypothalamic oxytocin and vasopressin expression in chronically hypernatremic rats.

Sustained hyperosmolality increases the levels of hypothalamic oxytocin (OT) and arginine vasopressin (AVP) messenger ribonucleic acids (mRNAs). Gonadectomy is known to abolish this response (12,18). In this study we investigated whether thyroidectomy would alter OT and AVP mRNA levels in the hypothalamic paraventricular nucleus (PVN) of the hyperosmotically stimulated rat. Male Sprague-Dawley rats underwent thyroidectomy (hypothyroid) or sham thyroidectomy (euthyroid) at 7 weeks of age. Three weeks later hypothyroid and euthyroid animals were administered 2% NaCl (6-11 days) or tap water and sacrificed at the end of the experiment. Northern blot hybridization was used to assess size and levels of hypothalamic OT and AVP mRNAs. Hypothyroid rats had significantly lower levels of serum thyroxine (T4) than their euthyroid cohorts (P < 0.0001). Both the euthyroid and the hypothyroid animals receiving 2% NaCl developed hypernatremia and increased the levels and the size of OT and AVP mRNAs compared to their tap water cohorts. We conclude that in contrast to gonadectomy, thyroidectomy does not alter the level of OT and AVP mRNAs in the hypothalamus of chronically hypernatremic male rats.

Animals↗