Participation of the superior ovarian nerve in the regulation of compensatory ovarian hypertrophy: the effects of its section performed on each day of the oestrous cycle

1994 ◽  
Vol 140 (2) ◽  
pp. 197-201 ◽  
Author(s):  
R Chávez ◽  
R Domínguez
Keyword(s):  
Left Ovary ◽  
Oestrous Cycle ◽  
Ovulation Rate ◽  
Adult Rats ◽  
Superior Ovarian Nerve ◽  
Neural Information ◽  
The Mean ◽  
The Right

Abstract The effects were analysed of section of the superior ovarian nerve on compensatory ovulation and ovarian hypertrophy, in adult rats with the left or right ovaries extirpated during the oestrous cycle and autopsied 6 or 20 days later. Rats with hemiovariectomy or hemiovariectomy plus denervation recovered their oestrous cyclicity between 2 and 3 days after surgery. Six days after hemiovariectomy 14 out of 17 rats ovulated on the expected day of oestrus. All the animals were hemiovariectomized on the day of pro-oestrus. The mean ± s.e.m. number of ova shed was similar to the group of animals with both ovaries (7·8 ± 1·2 vs 9·5 ± 0·2 Compensatory ovarian hypertrophy was observed in the right ovary when left hemiovariectomy was performed on day 2 of dioestrus or pro-oestrus; similar results were observed in the left ovary when the right one was extirpated at oestrus or pro-oestrus. Section of the right superior ovarian nerve in left-hemiovariectomized rats caused a reduction in ovulation rate and number of ova released. Compensatory ovarian hypertrophy was modified in the opposite way by unilateral section of the superior ovarian nerve to the in situ ovary depending on the day of the cycle when hemiovariectomy was performed. Twenty days after treatment, ovulation rate, compensatory ovulation and ovarian hypertrophy were similar in both left- or right-hemiovariectomized rats. Compensatory ovarian hypertrophy increased in all animals with section of the superior ovarian nerve, except when hemiovariectomy was carried out at oestrus or the left ovary was extirpated on day 1 of dioestrus. The results suggest that modulation of compensatory ovarian hypertrophy by neural information arriving at the ovary by way of the superior ovarian nerve varies during the oestrous cycle. Journal of Endocrinology (1994) 140, 197–201

Differential effects of a unilateral hypothalamic lesion on ovulation and compensatory ovarian hypertrophy in hemiovariectomized adult rats

1990 ◽  
Vol 124 (1) ◽  
pp. 37-41 ◽  
Author(s):  
M. E. Cruz ◽  
J. L. Moran ◽  
L. P. Jaramillo ◽  
R. Domínguez
Keyword(s):  
Hypothalamic Lesion ◽  
Anterior Hypothalamus ◽  
Left Ovary ◽  
Ovulation Rate ◽  
Unilateral Lesion ◽  
Adult Rats ◽  
Differential Effects ◽  
Medial Hypothalamus ◽  
The Right

ABSTRACT The effects were analysed of a unilateral lesion in the anterior or medial hypothalamus made on the day of oestrus on right or left hemicastrated rats. On the day of oestrus after two consecutive oestrous cycles of the same length, the ovulation rate in rats with lesions in the anterior left hypothalamus was lower than in control hemicastrated animals (5/16 vs 18/20; P<0·01), and normal in those rats with lesions in the right side (14/18). None of the animals with lesions in the left side of the anterior hypothalamus and with the left ovary in situ ovulated (0/7), but 5/9 with the right ovary in situ did ovulate (P<0·05). Lesions on either side of the medial hypothalamus did not modify ovulation rate. Compensatory ovulation was reduced in those animals with lesions in the right anterior hypothalamus and with the right ovary in situ. Lesions in either side of the medial hypothalamus reduced compensatory ovulation. Lesions in the right side of the anterior and medial hypothalamus increased compensatory ovarian hypertrophy in the left ovary and decreased it in the right ovary. Lesions in the left side of the anterior hypothalamus increased compensatory ovarian hypertrophy in the left ovary only, whereas lesions in the left side of the medial hypothalamus reduced compensatory ovarian hypertrophy in the right ovary. The results suggest that the information arising in each side of the anterior and medial hypothalamus plays different roles in the ipsi-and contralateral ovary, when either the left or the right ovary is absent. Journal of Endocrinology (1990) 124, 37–41

scholarly journals Effects of unilateral or bilateral superior ovarian nerve section in prepubertal rats on the ovulatory response to gonadotrophin administration

1998 ◽  
Vol 158 (2) ◽  
pp. 213-219 ◽  
Author(s):  
L Morales ◽  
R Chavez ◽  
ME Ayala ◽  
R Dominguez
Keyword(s):  
Hormonal Treatment ◽  
Left Ovary ◽  
Ovulation Rate ◽  
Neural Pathways ◽  
Exact Probability ◽  
Superior Ovarian Nerve ◽  
Prepubertal Rats ◽  
Left And Right ◽  
Left Section ◽  
The Right

The modulating effects of ovarian innervation reaching the ovary through the suspensory ovarian nerve on the reactivity of the ovaries to gonadotrophins were analysed. Juvenile rats (32 days old), with or without unilateral or bilateral section of the superior ovarian nerve, were injected with 8 iu of pregnant mare serum gonadotrophin (PMSG), 10 iu of human chorionic gonadotrophin (hCG) or with 8 iu of PMSG followed 56 h later with 10 iu of hCG. Treatments were given immediately after surgery or 4 days later, and the rats were killed on the day of first vaginal oestrus. In rats with unilateral section, treatment with PMSG did not induce full ovulatory response by the denervated ovary whether the treatment was applied immediately or 4 days after surgery (0/11 rats treated immediately ovulated vs 5/5 (sham) and 11/12 (control, P < 0.05 Fisher's exact probability test), and 4/19 did when treatment was done 4 days after surgery vs 8/10 (sham) and 11/12 (control, P < 0.05). The rats with bilateral section receiving the same hormonal treatment, PMSG administration, ovulated. The number of ova shed by the left ovary was similar to those of the control, while the right ovary released fewer ova. Stimulation with hCG immediately after unilateral section did not induce ovulation in normal or denervated ovary. When the treatment was applied 4 days after surgery, ovulation was observed only in the innervated ovary. In the rats with bilateral section, hCG injection induced ovulation in both ovaries. In those rats with unilateral section of the superior ovarian nerve, the treatment with PMSG + hCG given immediately after surgery resulted in a compensatory ovulation by the innervated ovary (the number of ova shed/ovulating animal was significantly higher than those released by control or sham-operated animals: left section, number of ova shed by the right ovary 7.6 +/- 0.3 vs 5.5 +/- 0.8 and 4.9 +/- 1 respectively, P < 0.05; right section, number of ova shed by the left ovary 10.2 +/- 0.6 vs 4.4 +/- 1.1 and 7.0 +/- 0.9, P < 0.05), while the denervated one showed a lower ovulation rate as well as a smaller number of ova shed than those by the control animals. When the hormonal replacement was given 4 days after surgery, such compensatory ovulation was observed in the left ovary of those rats with a section of the right nerve (14.3 +/- 2.6 vs 4.4 +/- 1.1 and 6.5 +/- 1.1, P < 0.05). When the PMSG + hCG treatment was applied to animals with bilateral section of the superior ovarian nerve, the ovulation rate by the right ovary was significantly lower than in control and sham-operated treated animals (2/10 vs 11/11 and 6/7, P < 0.05). Because the ovaries receive innervation through the superior ovarian nerve, the ovarian plexus and the vagus nerve, the results obtained in unilateral denervated animals suggest that the innervation of the ovary via the superior ovarian nerve regulates in a stimulatory way the effects of gonadotrophin resulting in ovulation. The ovulation induced by hormonal treatment of rats with bilateral section of the superior ovarian nerve suggests that the effects of bilateral section on ovulation are not the addition of the effects of left and right denervation, implying the existence of a modulatory effect in gonadotrophin action on ovulation via other neural pathways.

Differences in the ovulation rate of the right or left ovary in unilaterally ovariectomized rats: effect of ipsi- and contralateral vagus nerves on the remaining ovary

1987 ◽  
Vol 113 (3) ◽  
pp. 397-401 ◽  
Author(s):  
R. Chávez ◽  
M. E. Cruz ◽  
R. Domínguez
Keyword(s):  
Vagus Nerve ◽  
Left Ovary ◽  
Ovulation Rate ◽  
Ovariectomized Rats ◽  
Vagus Nerves ◽  
Regulatory Systems ◽  
Neuroendocrine Mechanisms ◽  
The Right ◽  
Left Vagus

ABSTRACT The possible existence of peripheral asymmetry in the neuroendocrine mechanisms participating in the response of the ovary to gonadotrophins, and the participation of the vagus nerve, was investigated. At oestrus, the ovulation rate (number of ovulating/number of treated rats) of the left ovary in right unilaterally ovariectomized rats was lower than that in the right ovary in left unilaterally ovariectomized rats (42 vs 84%). No differences in the number of ova shed per ovulating animal nor in compensatory ovarian hypertrophy (COH) were observed. Bilateral section of the vagus nerve resulted in reduced COH only in those animals with the left ovary in situ (right unilaterally ovariectomized). Section of the left vagus nerve induced different effects depending upon which ovary was left in situ. When the left ovary was in situ an increase in ovulation rate, COH and number of ova shed was observed; however, when the right ovary was left in place the above three parameters decreased. Section of the right vagus nerve produced a decrease only in COH in both right and left unilaterally ovariectomized animals. It is concluded that in the unilaterally ovariectomized rat the right ovary seems more able to react to compensatory regulatory systems than does the left. The character of the information carried by the left and right vagus nerve is different. J. Endocr. (1987) 113, 397–401

Differential ovulatory responses of the right and left ovaries of the adult rat to unilateral lesion and anaesthesia of the cervico-vaginal plexus

1990 ◽  
Vol 124 (1) ◽  
pp. 43-45 ◽  
Author(s):  
R. Domínguez
Keyword(s):  
Left Ovary ◽  
Oestrous Cycle ◽  
Ovulation Rate ◽  
Unilateral Lesion ◽  
Group 14 ◽  
Adult Rat ◽  
The Right ◽  
Do So

ABSTRACT Differences were observed in the ovulation rates of the right and left ovaries in response to unilateral lesions of the cervico-vaginal plexus (CVP) followed by pseudopregnancy or by anaesthesia of the CVP induced with panthocaine plus adrenaline (right ovary 6·7±0·4 (s.e.m.) vs left ovary 4·6 ± 0·9; P<0·05). Pseudopregnancy (days showing a dioestrous smear after copulation with a vasectomized male before an oestrous smear following a pro-oestrous one) lasted longer in rats with a lesion in the CVP than in a control pseudopregnant group (14·9 ± 0·5 vs 11·2 ± 0·5; P < 0·01). Anaesthesia of the CVP performed on each day of the oestrous cycle did not modify the ovulation rate compared with laparotomized animals. Both laparotomy and anaesthesia of the CVP performed on oestrus or day 1 of dioestrus blocked ovulation but when they were performed on day 2 of dioestrus or pro-oestrus they failed to do so (laparotomy 9/18 vs 12/14, P<0·05; anaesthesia of CVP 3/11 vs 17/17, P < 0·05). The number of ova shed by the left ovary in animals with anaesthetized CVP was lower than by the right ovary (4·5 ± 0·6 vs 6·2 ± 0·5; P<0·05). These results add further support to the idea that the CVP participates in the regulation of ovulation rate, and that the left ovary is less adaptable than the right when innervation is challenged. Journal of Endocrinology (1990) 124, 43–45

Effects on oestrous cyclicity and ovulation of unilateral section of the vagus nerve performed on different days of the oestrous cycle in the rat

1989 ◽  
Vol 123 (3) ◽  
pp. 441-444 ◽  
Author(s):  
R. Chávez ◽  
S. Sánchez ◽  
A. Ulloa-Aguirre ◽  
R. Domínguez
Keyword(s):  
Vagus Nerve ◽  
Plasma Levels ◽  
Vagal Nerve ◽  
Left Ovary ◽  
Oestrous Cycle ◽  
Ovulation Rate ◽  
Nerve Section ◽  
The Right ◽  
Left Vagus

ABSTRACT The effects of unilateral section of the right or left vagus nerve (SRVN, SLVN) performed on different days of the oestrous cycle of the rat were analysed. Vagal nerve section on the day of oestrus or on day 1 of dioestrus (D1) altered oestrous cyclicity in a more significant way than when it was performed on day 2 of dioestrus (D2) or pro-oestrus (6/58 maintained normal oestrous cycles compared with 32/39 that did not; P<0.01). Ovulation rate at oestrus was lower in rats with SLVN than in the sham-operated group (32/47 vs 28/32; P < 0.05). The number of ova shed by the left ovary was reduced in sham-operated rats and in animals with SRVN and SLVN, whereas the number shed by the right ovary was not modified. The day of the oestrous cycle on which the vagus nerve was cut also influenced the number of ova shed. No changes in plasma levels of FSH at oestrus were observed in animals with SRVN or SLVN. The results indicate that vagal manipulations performed at the beginning of the oestrous cycle (day of oestrus and D1) induce more changes on oestrous cyclicity and ovulation than when they are performed during the second half of the cycle (D2 and pro-oestrus). In addition, the left ovary is more sensitive to neural manipulation than is the right one. Journal of Endocrinology (1989) 123, 441-444

Short-term undernutrition and prenatal mortality in young and mature Merino ewes

1975 ◽  
Vol 84 (1) ◽  
pp. 113-117 ◽  
Author(s):  
A. J. Mackenzie ◽  
T. N. Edey
Keyword(s):  
Ovulation Rate ◽  
Control Group ◽  
Corpora Lutea ◽  
Short Term ◽  
Embryo Survival ◽  
Body Weights ◽  
Cycle Lengths ◽  
The Mean ◽  
Group 2 ◽  
The Right

SUMMARYPrenatal mortality was examined in 74 primiparous Merino ewes which, after hand mating to fertile rams on the second oestrus following synchronization, were allocated to two groups. One group of 38 ewes was confined to yards and restricted to approximately 30% of their maintenance requirement for 14 days while the other group of 36 remained at pasture. The degree and timing of prenatal loss was assessed by corpora lutea counts, pregnancy diagnosis about day 40, returns to service and lambing records.The mean ovulation rate was 1·06 and the 19-day non-return rate was 87·8%. Pregnancy failed in a higher proportion of the underfed ewes (45·0%) than in the control ewes (30·8%) but this difference did not reach significance. Of the ewes returning to service, significantly more did so with cycles longer than 19 days in the underfed group (9/12) than in the control group (2/8), indicating that in the latter stages, the treatment may have been detrimental to embryo survival.In a second experiment, ovulation rate and prenatal mortality, assessed as in the first experiment, were studied in 85 mature Merino ewes subjected to the following nutritional treatments: HH, control; HL, 30% submaintenance feeding for 14 days following mating; LH, 15% submaintenance feeding for 7 days prior to mating; LL, both submaintenance treatments.Acute undernutrition prior to mating (LH) had no effect on ovulation rate or prenatal mortality. Ovulation rates were low over all groups (mean 1·09) and thus precluded any valid examination of ovulation rate and body weight relationships. The right ovary was significantly more active in producing ova than the left in all groups (P < 0·05). Although ova wastage was apparently higher in. the post-mating undernutrition groups (HL, 44%; LL, 48%; LH, 50%) than in the control group (HH, 35%), the differences were not significant. An increased incidence of extended (> 19 days) first-return cycle lengths in group LL provided some evidence of induced prenatal mortality.In so far as the experiments can be considered together, they indicate that if body weights are comparable, primiparous 1½-year-old ewes are not necessarily more susceptible than mature ewes to prenatal mortality induced by severe short-term undernutrition.

scholarly journals The Phases of the Oestrous Cycle in the Adult White Rat

1951 ◽  
Vol 28 (4) ◽  
pp. 576-584
Author(s):  
ANITA M. MANDL
Keyword(s):  
Cycle Length ◽  
The Body ◽  
Oestrous Cycle ◽  
Adult Rats ◽  
Significant Fluctuation ◽  
The Mean

The duration of the oestrous cycle in thirty-nine adult rats derived from ten litters was 4.4 ± 0.04 days. The variance in cycle length tended to be less within than between litter-groups (P≏0.05). It was significantly less for individual rats than between individuals (P&lt;0.001). The mean duration of early oestrus was 18 hr., oestrus 25 hr., late oestrus 5 hr., early dioestrus 24 hr., dioestrus 28 hr. and late dioestrus 7 hr. The length of the dioestrous phase is variable and determines the length of the cycle, while the duration of oestrus appears to be relatively constant. The figures have been compared with those published by other laboratories. Analyses of variance did not disclose any significant fluctuation in the weight of the body, adrenals or ovaries in phase with the oestrous cycle. The uterus showed a characteristic increase in weight immediately before the onset of oestrus.

Mechanical properties of muscle units in the cat diaphragm

1988 ◽  
Vol 59 (3) ◽  
pp. 1055-1066 ◽  
Author(s):  
M. Fournier ◽  
G. C. Sieck
Keyword(s):  
Contractile Properties ◽  
Fatigue Properties ◽  
Tetanic Force ◽  
Wide Range ◽  
The Mean ◽  
Slow Twitch ◽  
The Right ◽  
Fast Twitch ◽  
Tetanic Tension

1. Muscle units in the right sternocostal region of the cat diaphragm (DIA) were isolated in situ by dissecting filaments of the C5 ventral root. Isometric contractile and fatigue properties of DIA units were then measured. Contractile properties included: twitch contraction time (CT), peak twitch tension (Pt), maximum tetanic tension (P0), and the frequency dependence of tension production. Muscle-unit fatigue resistance was estimated using a 2-min fatigue test. 2. DIA muscle units were classified as fast (F) or slow (S) based on the presence or absence of sag in their unfused tetanic force responses. Muscle-unit fatigue indices (FI) were used to further classify DIA units as slow-twitch fatigue-resistant (S), fast-twitch fatigue-resistant (FR) fast-twitch fatigue-intermediate (FInt), or fast-twitch fatigable (FF) types. 3. Based on a total of 47 completely characterized DIA muscle units, 21% were classified as S, 4% as FR, 28% as FInt, and 47% as FF. In contrast to the distribution of unit types in other mixed appendicular muscles, the DIA was composed of a very low proportion of FR units and a relatively high proportion of FInt units. An interval of FIs between 0.50 and 0.75 separated units into fatigue-resistant and fatigable groups. The distribution of FIs for FF and most FInt units was continuous, indicating that they formed a single fatigable group. Relatively few FF units in the DIA had FIs less than 0.10. 4. A wide range of contractile properties was observed for DIA muscle units. Type S units had longer CTs and lower Pt and P0 values than type F units. The mean Pt and P0 of FF and FInt units were comparable, whereas the mean Pt and P0 of the two FR units were lower. Type S units produced a greater proportion of their P0 at lower frequencies of activation than type F units. The lower P0S produced by type F units in the DIA indicated that they were smaller than similar units in appendicular muscles. It was concluded that in meeting most normal ventilatory requirements, adequate force could be generated by the recruitment of only type S and FR units. The recruitment of the more fatigable FF and FInt units may occur only during more forceful respiratory and nonrespiratory behaviors of the DIA.

The GraftConnector Experience

Swiss Surgery ◽  
2001 ◽  
Vol 7 (5) ◽  
pp. 209-210 ◽  
Author(s):  
Piergiorgio Tozzi ◽  
Jan Otto Solem ◽  
Boumzebra ◽  
Antonio Mucciolo ◽  
Xavier Mueller ◽  
...  
Keyword(s):  
Internal Mammary Artery ◽  
Long Term Results ◽  
Sheep Model ◽  
Adult Sheep ◽  
Internal Mammary ◽  
The Mean ◽  
The Right

Background: A device to perform sutureless end-to-side coronary artery anastomosis has been developed by means of stent technology (GraftConnector). The present study assesses the long-term quality of the GraftConnector anastomosis in a sheep model. Methods: In 8 adult sheep, 40-55kg in weight, through left anterior thoracotomy, the right internal mammary artery (RIMA) was prepared and connected to the left anterior descending artery (LAD) by means of GraftConnector, on beating heart, without using any stabiliser. Ticlopidine 250mg/day for anticoagulation for 4 weeks and Aspirin 100mg/day for 6 months were given. The animals were sacrificed after 6 months and histological examination of anastomoses was carried out after slicing with the connector in situ for morphological analysis. Results: All animals survived at 6 months. All anastomoses were patent and mean luminal width at histology was 1.8 0.2mm; mean myointima hyperplasia thickness was 0.21 0.1mm. Conclusions: Long-term results demonstrate that OPCABGs performed with GraftConnector had 100% patency rate. The mean anastomotic luminal width corresponds to mean LAD's adult sheep diameter. We may speculate that myointima hyperplasia occurred as a result of local device oversizing.

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